by BendPak
POSITION THAT RELUCTOR WHEEL FOR PRECISE TIMING
If not timed correctly relative to the crank’s rod throws, the engine either won’t fire at all or it will run severely out of time.
24
TRITON
Stronger in numbers. Add yourself to the equation. Miguel isn’t one to ask for help. Equipped with The TRITON™, which provides verified fixes harvested from users across the globe, he doesn’t have to. Offering a 2-channel lab scope and wireless connection, it’s like having 70 thousand techs, each with 40 years of experience at his side. So you can cover Miguel’s back, and he’ll cover yours. Plus up your numbers with the diagnostics system that adds you to the equation.
12 Removing Resistance From Your Routine
An ohmmeter that passes a test doesn’t guarantee circuit health—dynamic load testing is the key to catching failures that static measurements miss Brandon Steckler
18 Why Wheel Alignment Has Become Critical to ADAS Performance
As vehicles rely increasingly on sensors and cameras for safety systems, technicians must understand that proper alignment is the foundation of everything
Erik Screeden
24 Installing a LS Crankshaft Reluctor Wheel
A step-by-step guide to correctly positioning the reluctor wheel for precise timing
Mike Mavrigian
32 Turbo Diagnostics
A structured approach to understanding sensor data, wastegate control, and system diagnostics for modern turbocharged engines
Jeff Taylor
38 A Pro’s Guide to Preload and Clamping Force
Going from subjective tightening to measurable, repeatable procedures that satisfy customers and reduce comebacks
Noah Nelson
42 What 50 Years of Emissions Science Has Taught Us
Understanding the significance of science and technological progress at the intersection of automotive repair and environmental responsibility
Craig Van Batenburg
TOOLBOX
December) by Endeavor Business Media, LLC. 201 N Main St 5th Floor, Fort Atkinson, WI 53538. Customer service can be reached toll-free at 877-382-9187 or at MotorAge@omeda.com for magazine subscription assistance or questions. Printed in the USA. Copyright 2026 Endeavor Business Media, LLC. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopies, recordings, or any information storage or retrieval system without permission from the publisher. Endeavor Business Media, LLC does not assume and hereby disclaims any liability to any person or company for any loss or damage caused by errors or omissions in the material herein, regardless of whether such errors result from negligence, accident, or any other cause whatsoever. The views and opinions in the articles herein are not to be taken as official expressions of the publishers, unless so stated. The publishers do not warrant either expressly or by implication, the factual accuracy of the articles herein, nor do they so warrant any views or opinions by the authors of said articles.
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WE’RE EXPANDING OUR NETWORK
We’ve rebranded our YouTube channel to unite all vehicle service and repair content under one authoritative platform. The new Vehicle Service & Repair Video Network consolidates expert training, diagnostics, and industry intelligence from Motor Age, Professional Tool & Equipment News, Ratchet+Wrench, and seven other leading brands. Designed for today’s technicians navigating ADAS, EV technologies, and complex diagnostics, the channel delivers best-in-class technical content for service professionals.
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HOW MODERN BATTERY DIAGNOSTICS EXPOSE HIDDEN FAILURES
Think a fully charged battery is a healthy battery? Think again. In this Motor Age Tech Tip Short, Erik Screeden reveals why sulfation, heat, vibration, and age silently rob batteries of their ability to deliver power—even when they test as fully charged. Learn why today’s high-demand vehicles demand you check both state of charge and state of health to prevent costly starting and charging system failures.
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The Captain Friendly Legacy: How One Shop Turned Roadside Service Into Marketing Gold
Before cell phones and roadside assistance apps, a New York repair shop’s free roadside service program became a community lifeline—and a business builder
BACK IN THE 1980S, I visited a repair shop and tire dealer in western upstate New York that operated a unique public service that doubled as a powerful marketing tool. They had a dedicated full-size van emblazoned with their store logo and fully equipped to render roadside service for stranded vehicles. Dubbed the “Captain Friendly” van, the vehicle routinely patrolled local highways searching for motorists in distress.
The van’s secret weapon was constant radio contact with a local news station that operated a traffic helicopter. During the chopper’s news reports on local traffic flow and congestion, when the helicopter’s traffic reporter spotted a vehicle in trouble, he contacted the Captain Friendly driver with the location. The van then made its way to the scene.
The van was equipped with spare gasoline, jacks and jack stands, hand and pneumatic tools (including an onboard air compressor), battery chargers, spare drive belts in miscellaneous sizes, engine coolant, engine oil, transmission fluid, and other supplies— whatever might get a troubled vehicle back on the road. And the roadside aid was provided free of charge.
If the vehicle could not be emergency-repaired roadside, Captain Friendly
would notify a tow truck and wait with the stranded motorist until it arrived. While there was no requirement for the vehicle to be towed to the parent shop, in the majority of cases, drivers chose that location due to their appreciation for the free roadside help and the technician-driver’s professionalism.
There were many breakdowns on busy local highways, especially during harsh winters and heavy congestion. Stranded motorists were extremely grateful for the assistance.
The program earned the service shop substantial favorable publicity and made them a local hero for their generous public service. From a business standpoint, the program generated a significant increase in revenue and customer loyalty from both those who received help and the general public, impressed by the shop’s Good Samaritan reputation.
ADAPTING THE MODEL FOR TODAY’S SHOP
Not all shops can spare a vehicle, technician, and parts inventory to implement such a comprehensive program, but it’s worth considering both from a community service standpoint and for generating favorable publicity.
If inspired by the Captain Friendly concept, consider launching a limited
service during specific times of year— high summer traffic periods, snow storm seasons, or major holiday travel weekends. It’s a worthwhile investment. Granted, this predates the cell phone era. Although motorists today can easily call for assistance, this type of program remains valuable. Contact your local news outlets that operate traffic helicopters or traffic monitor ing services to explore whether such a cooperative public service arrangement makes sense for your market area.
MIKE MAVRIGIAN MOTOR AGE // EDITOR mmavrigian@endeavorb2b.com
A versatile choice for mixed fleets, BendPak’s new 16AP and 20AP Series heavy-duty two-post lifts easily take on Class 1 through 5 vehicles, from passenger cars to commercial trucks and vans. They reach further, lift higher and deliver greater stability than other lifts, all while protecting technicians with unmatched safety systems and ergonomics. With fewer moving parts, they’re easier to maintain, less prone to wear, and more cost-effective to operate. Maximize your uptime and efficiency with BendPak’s heavy-duty lifts — delivering superior performance and unmatched value. To learn more or to shop now, visit bendpak.com or call us at 1-800-253-2363
Mazda Cracks
Connecting Rod Bend/Twist
Be aware that some 2019-2020 Mazda CX-5 SKYACTIV-G 2.5L turbo vehicles built before June 9, 2020, may exhibit coolant leaks at the cylinder head around the exhaust manifold. There may be cracks at the stud bolt hole or at the outside of the exhaust manifold flange on the cylinder head. The cracks may be caused by expansion of the exhaust manifold and by residual stress generated during production of the cylinder head material. The external force from the exhaust system when driving over bumps may cause unexpected force to certain areas of the cylinder head. Mazda has since modified the design of the exhaust manifold gasket and the cylinder head. Inspect the DTC P111A. If that code is stored, engine overheating is suspected. The repair involves replacing the cylinder head with P/N PYY1-10-SJ0, and gasket sets PYY110-S50 and PYY1-13-S50.
Connecting rod alignment (twist) can be checked on a rod alignment checking stand to determine if the rod beam has bent or twisted. With the big end held in register, the checking stand’s upper anvil rests on top of the wrist pin to check for rod bend (a feeler
USING A CONNECTING ROD alignment checker, inspect each connecting rod for bend (with the rod placed onto the tool centering fixture, a feeler gauge can be used between the wrist pin surface and the upper checking base).
gauge is inserted between the wrist pin and anvil on each side of the rod’s small end). To check the rod for twist, the anvil is positioned behind the wrist pin, using a feeler gauge at each side. Generally speaking, the maximum allowable twist is 0.001”.
CHECK EACH ROD FOR twist (small and big end bore centerlines at different planes). Rod bend or twist should be less than 0.001” for every inch of rod length. For example, a connecting rod length of 6” to 6.2” should not have more than 0.006” bend or twist. Depending on OE specifications, the maximum allowable bend or twist might be tighter at about 0.004” to 0.005.”If the bend or twist is greater than the maximum allowable spec, replace the connecting rod. Do not attempt to straighten a bent or twisted rod.
PHOTOS BY MIKE MAVRIGIAN EXAMPLE
Troubleshooting Trailer Brakes/ Controllers
If a customer complains about the braking system on their trailer not working or not working reliably, here are a few checkpoints.
Measure voltage at the tow vehicle socket. If low voltage is present, turn the gain control on the controller up all the way. If full voltage is not present, check volts at the controller output. If full voltage is not present, then the controller needs to be replaced.
F-150 DTCs
2022-2024 Ford F-150 trucks may experience inoperative Bluecruise and lane centering with DTCs U2018-51 stored in the CMR and U0565-86 stored in the IPMA. This may be due to the software in the CMR. Simply reprogram the CMR using the latest software level of the FDRS scan tool.
If full voltage is present at the socket on the vehicle next test is the trailer itself. With the trailer hooked up, have a helper apply the override on the controller. Measure the voltage at the axles on each backing plate. If the measurement is full or near full voltage (some voltage drop is normal), the problem lies within the electromagnet or brake shoes. Magnets can be checked for continuity when the drums are pulled.
If low or no voltage is present, perform a trailer ground test by using a jumper wire of at least 10 gauge. Repair the ground as needed. If the ground is not the issue, assume that the trailer wiring needs to be repaired/ replaced. Tip: The use of 10 gauge (or greater) is recommended. Avoid using 12 gauge or smaller.
Old Trick for Valve Seal Service
When replacing valve stem seals on a cylinder head (without removing the cylinder head), remove the spark plug from a cylinder and fill the cylinder with compressed air (one way is to remove the gauge from a compression tester and install the tester’s threaded end into the spark plug hole, then connect shop air to the hose). This keeps the valve fully closed and prevents it from dropping while you change the seal. It’s an old and simple time-saving trick, but it’s worth remembering. An on-the-head valve spring compressor is needed to remove/install the spring.
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Why Voltage Drop Testing Reveals Hidden Electrical Faults
An ohmmeter that passes a test doesn’t guarantee circuit health—dynamic load testing is the key to catching failures that static measurements miss
BY BRANDON STECKLER
RESISTANCE MEASUREMENTS can offer a quick path to successful diagnosis, or a long walk home with your tail between your legs. It’s all in what you make of it. I remember a time when a coworker was bitten by the results of a resistance measurement, not yet hip to the fact that testing an unloaded circuit could leave a few stones unturned. This simple misinterpretation of data cost the shop nearly $1,000, and the embarrassed technician a gauntlet of ridicule for days to follow.
It’s unfortunate that the lessons we tend to learn in our corner of the world are usually achieved only in real-world conditions and tend to be either costly, embarrassing, painful, or often a combination of the three.
So It Begins
I recall it like it was yesterday, my first real purchase of diagnostic equipment. I was 18 years old and was in the early stages of Specialized Electronics Training put on by GM Automotive Service Educational Program. I had just purchased my new Fluke 87A.
We set our DVOMs to “resistance/continuity,” like excited toddlers attracted to the audible feedback, and shunted the test leads together. More than 20 meters rang out in harmony, like bikers twisting the throttles at a stoplight. I’m not sure why that was exciting to us, but it made me feel like I was progressing toward being a real professional technician.
Days into the course, and we were implementing the DVOM in many facets. As we created and tested against an assortment of circuit combinations, the information our instructor passed along to us became clearly evident as the tests were conducted.
One of the test results most easily seen and interpreted was a test for resistance across a cigarette lighter circuit. The resistance through the circuit was measured with the circuit in both an “open” and a “closed” state. These easy-to-interpret test results gave confidence that the
test was a reliable one to carry out in a testing routine. Perhaps a little too much confidence (Figure 1).
The Application of Ohm’s Law
One of the most basic laws of electricity that all technicians must grasp is Ohm’s law. Cutting past the technical jargon that many get hung up on (and discouraged by), Ohm’s Law describes the relationship between:
• Voltage (electrical potential/ electrical pressure)
• Amperage (electrical current/flow of electrons through a circuit)
• Resistance (the opposition to that flow of electrons)
Regarding the direct current circuitry found in the vehicles we see each and every day, there are characteristics that we learn to become familiar with and rely heavily upon, regarding Ohm’s Law.
• When resistance remains unchanged, an increase in voltage (electrical pressure) will create more flow of electrons (more current). Just like a decrease in voltage will reduce the flow of electrons.
• If the voltage remains unchanged, an increase in resistance will reduce current flow. Of course, the opposite holds if the amount of resistance decreases.
• If the current remains unchanged and resistance increases, the voltage must have increased as well. Again, the opposite holds.
Simple concepts like these are easy to see, especially when staring at pictures like this helpful cartoon (Figure 2). I think this is a huge reason why so many rely so heavily on resistance measurements.
The good news is that when resistance measurements fall outside of specification, a fault is present and is being
displayed by the ohmmeter. The problem is that not all faults will be visible with an ohmmeter.
The Fuel Pump That Couldn’t
A real-world example from what I’m describing is one from nearly 15 years ago. A good friend of mine is an excellent nuts-and-bolts type of technician; he can repair anything. But when it comes to diagnostics (particularly electrical troubleshooting), he concedes to his shortcomings.
A 2006 Honda Odyssey was towed to
the shop with a complaint that the engine lost power while driving. The engine stalled on the side of the road and would then only crank/no-start.
Upon placing the vehicle in the work bay, the tech quickly determined the fuel pump was not functioning. After removing a panel to access the fuel pump, the connector was removed from the pump assembly, and the technician tested for available voltage and ground. As the key was cycled, full electrical potential (about 12.5V) was present during the 2-second prime, and at about 10V while
the starter was energized to crank the engine (a normal and expected result) (Figure 3).
Following his test results, the technician removed the fuel pump to ensure fuel was present in the tank. Upon confirmation, he then replaced the fuel pump. The engine failed to start, and again, the fuel pump was not functioning. Performing the same test, the technician confirmed sufficient voltage and ground availability at the terminals of the disconnected fuel pump connector.
Confused, the technician reached out for help (realizing the limitations of his knowledge base). From afar, it was suggested to him that the test he performed was not necessarily revealing of a fault and that a dynamic test would be more suitable. A bit perplexed, he then decided to measure the resistance of the open circuit, again only to find the results still pointing to a faulty fuel pump motor. At this point, I stopped over to offer assistance. Instead of measuring for available voltage and ground at an unmated connector, I instructed him to leave the connector mated as it would be during normal operation. I then suggested the circuits be monitored while attempting to operate the pump. This is what we refer to as a voltage drop test. A back-probing or pierce-probing of both circuits allows this test to be conducted.
Doing so allowed the voltmeter (not the ohmmeter) to display the amount of voltage “used up” across the intended load (the fuel pump). In a normally functioning circuit of this design, the fuel pump should use almost all of the available voltage across it. Armed with this anticipation, the expected meter reading (if the circuit was healthy) should have been in the neighborhood of 12.5V. The actual voltmeter reading displayed about 1.2V. The results displayed that the fuel pump only used up about 1.2V. That meant 11.3V was being wasted elsewhere. An insufficient ground, insufficient voltage supply, or high-resistance
FIGURE 1: This graphical representation of a cigar lighter is commonly used on electrical training test boards. The simple test result being displayed is a lack of continuity / infinite resistance as the circuit is open. Resistance should be present with the switch contacts closed.
PHOTO COURTESY OF BRANDON STECKLER
FIGURE 2: This cartoon demonstrates the relationship between voltage, amperage, and resistance. The definition of Ohm’s Law.
PHOTO COURTESY OF BRANDON STECKLER
that is only revealed when the circuit is loaded/attempting to operate (Figure 4).
Ohmmeter Construction
The reason the ohmmeter isn’t as reliable a tool as many make it out to be is how it functions to determine resistance. The internal circuitry of the meter (when measuring resistance) leverages the meter’s battery source to place a small electrical current (of a known value) on the circuit being measured. The resistance of the circuit being measured will create a voltage drop (just as Ohm’s Law prescribes). It’s this measured voltage drop that the ohmmeter will correlate to a resistance value, for display.
In essence, the ohmmeter uses the equation R=V/I (meaning, the resistance is equal to the resulting quotient of “measured voltage drop, divided by the known current flow used by the ohmmeter”) (Figure 5).
This is not to say that the results of a test conducted with an ohmmeter are inaccurate. It’s simply to say that we must always be cautious of resistance measurements that meet the specification. We must always realize the limitations of the test we are performing and the limitations of the tools used to display those test results.
A test that results in a “failure” can be trusted (if conducted properly). However, a test that results in a “pass” may still have an underlying fault that might only be revealed under more loaded conditions. These conditions typically require the circuit to be operated as intended, under dynamic conditions.
There is no better way to accomplish this than attempting to operate the circuit naturally and measuring for voltage drop (across the intended load) instead of an open-circuit resistance measurement with an ohmmeter. However, there will be situations where that may not be possible.
For instance, if that same fuel pump circuit fault was a result of a truly faulty pump (an open or extremely high inter-
elsewhere. This also means that more
nal resistance), current flow would be insufficient to load the rest of the circuit properly. Meaning, there may be a subsequent fault in the circuit supporting the operation of that pump, but there would be no way to load the circuit dynamically simply by operating the circuit as intended, because the circuit doesn’t work at that moment. This would require an outside source to adequately conduct a loaded voltage-drop test.
The Loaded Voltage-Drop Test
The loaded voltage drop test is typi -
cally conducted in a scenario when the circuit cannot be completed naturally (like when a relay closes, a transistor latches, or a button is depressed to close a switch contact).
Leveraging a device like this one from Joe’s Auto Electric allows you to simply combine the operation of anywhere from one through six bulbs simultaneously to load the circuit being tested. Each bulb pulls about 2.5 amps of current. Where four bulbs operating in parallel will pull about 10 amps of current, all six bulbs, in parallel, will pull nearly 15 amps. The
FIGURE 3: With the fuel pump connector unmated, the 12.5V present across the two supply terminals is deceiving. Although this value is correct, this static test doesn’t reflect the health of the circuit once a load is placed on it (when current is flowing through it).
PHOTO COURTESY OF BRANDON STECKLER
FIGURE 4: This dynamic voltage drop test display the importance of testing a circuit while it is energized. The 1.2V dropped across the fuel pump also means that 11.3V is being wasted
pinpointed testing for the fault location is justified.
PHOTO COURTESY OF BRANDON STECKLER
idea is to closely match the “normal load” that the circuit operates with when functioning as it should (Figure 6).
For example, when testing a tail lamp bulb circuit, only one bulb would need to be used to adequately load the supporting circuit on the suspect vehicle. However, a fuel pump would require the implementation of all six bulbs operating in parallel to load the supporting circuit adequately.
To use too small a load (like using only one bulb, when four should be used) may mean that the test you conduct shows the circuit capable of operating the smaller load. The voltage drop of that
single test bulb would glow brilliantly. Even if the circuit was compromised, you would never know it. If the circuit was tested adequately (with the four bulbs operating), they would easily reveal an underlying fault in the suspect supporting circuit of the intended device.
The irony in all of this is that even the ohmmeter (used to measure resistance) is truly conducting a voltage-drop test. I think that should be a sign that we need to be testing dynamically when evaluating components and the circuits they reside in. The proof is in the pudding.
When a properly conducted resistance test fails to show a problem, it’s simply because the ohmmeter uses such a small amount of current to carry out that test. This insufficient current amount is not enough of a load on the suspect circuit to flush the fault to the surface and reveal it.
It’s no different than sitting in a chair and having your blood pressure/heart rate monitored. An underlying fault may be present, but until you are running on a treadmill at a steep grade, that health condition may go undetected. Replace an inoperable component without properly load testing the supportive circuitry,
and the results may just give your boss heart failure.
So, to revisit the point of my sharing this information, the resistance test is one that is easily conducted and can be reli able when faults are revealed. However, the low current used by the ohmmeter to conduct the test can inadequately load the circuit and leave many faults undetected.
Begin to set the resistance test aside, and instead, perform a voltage-drop test across the intended load of the suspect circuit. If the circuit cannot be operated due to a faulty component, implement the loaded voltage-drop test (like described above). In either case, if your results display nearly the source voltage, rest assured of two things. Your supporting circuit is healthy, and the fault is lying right between your two test leads. If the test results across the intended load are sub-par, there is a supply issue on either the voltage-side or ground-side of that intended load. Now, go find it!
Please be reminded that all new tools and testing techniques take time and a willingness to practice. Do so on knowngood circuits and then conduct the same test on a suspect one. You’ll be delighted to learn just how much more accurate and efficient you will become. This, I can promise you!
BRANDON STECKLER is an ASE Master Technician (A1-A9, C1, and advanced level designations in L1, L2, L3, L4, and xEV-Level 2) and a certified instructor with expertise in automotive diagnostics and driveability. He earned GM Automotive Service Education cre dentials from Northampton County Community College. With more than 20 years of experience spanning dealerships and independent shops, he instructs at Carquest Technical Institute and Worldpac Training Institute, authors books and classes, and provides technical support through Steckler Automotive Technical Services.
FIGURE 6: This circuit load device from Joe’s Auto Electric (known as the “Load It”) is one of many on the market. This device allows you to simulate the load intended for the circuit and will flush faults to the surface.
PHOTO BY JOE CACI
FIGURE 5: The ohmmeter outputs a small current of a known value and measures voltage drop in the circuit. The idea is that resistance= voltage/amperage is Ohm’s Law. The problem is that this small current doesn’t load the circuits properly, and as a result, the resistance test frequently fails to indicate a circuit fault.
PHOTO COURTESY OF BRANDON STECKLER
Why Wheel Alignment Has Become Critical to ADAS Performance
As vehicles rely increasingly on sensors and cameras for safety systems, technicians must understand that proper alignment is the foundation of everything
BY ERIK SCREEDEN
SINCE THE EARLY DAYS of the automobile, wheel alignment has been an important part of vehicle service and repair. It has always been fundamental to vehicle handling, tire wear, and passenger comfort. But today, it has become an even more critical service that technicians provide their customers, and that is because of all the advanced driver safety systems that are incorporated into the modern vehicle. While ADAS systems should not be a foreign concept to today’s technician, it’s just as important for the technician to have a firm understanding
of the foundation these systems are built on, as well as the systems themselves. Modern vehicles are dependent on a network of sensors. Things like cameras, radar, LiDAR, and ultrasonic sensors are constantly interpreting the world around them. The vehicle needs to use the data these sensors provide to make split-second decisions about what is straight, level, centered, and moving. And the vehicle bases this all on one fundamental assumption: that the vehicle’s geometry is correct.
A Game of Inches
In the 2000 movie “The Patriot,” Mel Gibson’s character reminds his two young sons to “aim small, miss small” as they waited in ambush for a squad of British Red Coats. ADAS functionality relies on accuracy, and that system accuracy is dependent upon the foundation it’s built upon being true. A forward-facing radar module may be mounted correctly to its bracket, its bracket may be mounted securely and correctly to the radiator core support, and the vehicle can have a successful static calibration of that system. But if the thrust angle is off and the vehicle isn’t tracking straight down the road, the ADAS systems that rely on an input from that module will not work as effectively as designed. If that forward-facing radar module is even one degree off from the direction of travel, at 100 yards, that module will be off target by more than five feet. At 75 mph, that vehicle is traversing over 36 yards per second, so if you can see why accuracy is important.
Understanding the Technology
To understand why alignment geometry is so important for ADAS performance, it’s critical to understand how these systems operate. Every ADAS input— camera, radar, or sensor mounted to a vehicle—is going to be calibrated relative to that vehicle’s frame of reference. Basically, that vehicle’s centerline, thrust angle, and the level horizon.
When a technician performs a calibration on a forward-facing camera, for instance, they don’t just teach the system to recognize a pattern; they also help it define where straight ahead is, where the level horizon is, and what the vehicle considers centered in the lane. If the geometric assumptions the vehicle makes are correct, the ADAS module has a baseline that is reliable to interpret lane markings, oncoming traffic, pedestrians, and other obstacles. If they are not, then every decision the vehicle makes is based on that built-in error. Forward-facing cameras, radar modules, blind spot sensors, and 360-degree camera systems all depend to varying degrees upon accurate base alignment geometry and ride height. ADAS calibrations don’t just aim sensors; they help synchronize the ADAS system and the vehicle’s physical geometry, and geometry starts with alignment.
The Chain of Accuracy
ADAS accuracy does not start with target boards and a scan tool; it starts with the alignment rack. We have established that virtually every step in the calibration process depends on accurate alignment. Yet not all manufacturers call out a complete four-wheel alignment as step one in the calibration process, or they leave it as an optional step for the technician. Just because the repair a technician performed that triggered the need for an ADAS calibration does not call for a wheel alignment, does not mean that for certain calibrations the alignment should not be checked. How else would the technician know that the vehicle entered the bay with an accurate alignment to begin with? This falls back on the technician to have that firm understanding of system design and overall concept of operation. Remember, the alignment identifies the geometry, and inputs from systems like the steering angle sensor confirm the driver’s intent. It’s imperative that the alignment geometry is true and that proper steering angle resets have been
THE ADAS systems on today’s vehicles rely on multiple layers of technology to operate correctly. These multiple layers all need to be built on a solid foundation to achieve the safety coverage that the vehicle designers intended. Even the slightest deviation can have detrimental effects when it comes to system operation.
PHOTO BY SNAP-ON DIAGNOSTICS
WHEN YOU illustrate it, it’s a simple concept. For systems like long-range radar and forward-facing cameras to work, they need to be aimed in the same direction the vehicle is traveling. An accurate static calibration of a radar module will do no good if the vehicle is crabbing down the road.
GRAPHIC BY ERIK SCREEDEN
made before a target has been placed in front of a vehicle. This chain of events has to happen precisely and to the manufacturer’s specifications because when any link in the chain is compromised, the result is an ADAS calibration that appears to have completed successfully, but does not reflect the vehicle’s true driving di-
rection. There may not be a fault code set, but the vehicle will not interpret the road as it should.
Proper alignment, verified on level, calibrated equipment, is a critical first step in an ADAS calibration procedure. To treat an alignment as a separate or optional task is only inviting unnecessary risk and headache for the driver and technician.
The
Hidden Variables
Wheel alignment data doesn’t exist in isolation; this data is a product of suspension geometry, which itself is interdependent on vehicle ride height. For vehicles equipped with ADAS systems, ride height isn’t just about vehicle appearance or tire wear. It’s a direct input to how cameras, radar modules, and other sensors perceive the world. When the vehicle sits higher or lower than designed, every camera and sensor’s aim changes.
Forward-facing radar modules and cameras are calibrated precisely, and a change of a few millimeters in ride height will alter the camera or sensors’ aim by fractions of a degree, which is enough to alter its detection field significantly farther or shorter than intended. A vehi-
cle that is heavily loaded in the rear, for instance, is going to travel with a nose high angle of attack, effectively tilting the radar up as well. The radar is now aimed too high, affecting its short-range accuracy, and it could affect its ability to detect closer objects. The same geometry affects camera pitch angle, changing the way the camera interprets things like lane markings. Now, obviously, the loading of vehicles cannot be avoided, but if a vehicle is going to consistently be loaded, additional effort could be made to level that vehicle out under load, keeping equipped ADAS systems online and functioning as designed.
Inputs like ride height sensors are also key components in ADAS systems. A quick look in data stream to verify correct operation can alleviate future headaches for a technician. These sensors are feeding information to the ADAS system, and improper operation could cause an attempted compensation for a false pitch or roll condition.
Many OEM calibration procedures explicitly call for verification of ride height before starting the calibration process. But all too often this step is overlooked. Yet persistent calibration failures or inconsistent system performance can lead directly back to vehicle ride height.
Invisible Offenders
We have well established that inputs like the forward-facing camera and radar modules are dependent upon the vehicle’s thrust angle and centerline meshing up. We need the vehicle to travel in the direction the camera and radar are pointed at, or they won’t be effective in alerting us to dangers in the vehicle’s path.
Many technicians don’t spend enough time thinking about the vehicle holistically in terms of mechanical repair. It’s not unheard of for a technician to need to drop a rear cradle to gain enough room to pull a fuel tank to replace a pump module or replace a rear differential assembly. Any service that can change the rear toe
angles should have an alignment included with the quote, again, to make sure that the ADAS system is being built upon a square foundation.
Steering Angle Sensor, Thrust Angle, and the Vehicle’s Perception of Straight Ahead
If the thrust angle defines where the vehicle is actually going, the steering angle sensor defines what the vehicle thinks the driver wants to do. For vehicles equipped with ADAS, those two references, vehicle direction of travel and driver intent, must perfectly agree. If they don’t, then the system’s perception of straight ahead becomes distorted, and accuracy is affected.
The SAS is a key player for many ADAS functions. It feeds data to modules controlling lane keep assist, electronic stability control, adaptive cruise, and collision avoidance systems. Its ability to communicate steering rate, position, and torque over the high-speed network is at the heart of the vehicle’s ADAS system.
During ADAS calibration, the SAS value is critical. For accurate operation, the systems need to know where true zero is. The SAS provides the input to tell the vehicle when the wheels are pointed straight ahead, which should correspond with the vehicle’s thrust line and geometric centerline. But if the SAS system has failed to be calibrated after a previous alignment, the SAS input is misaligned with the vehicle’s true direction of travel.
That misalignment can create some subtle issues:
• Lane Departure Warning might trigger early on one side because the vehicle thinks it’s veering when it’s actually tracking straight
• Lane Keep Assist may try to constantly nudge the steering wheel to compensate for what it interprets as a drift
• Adaptive Cruise Control could track slightly out of the lane, detecting
ESTABLISHING ACCURATE ride height is an important part of the wheel alignment process. It’s important to follow manufacture service procedures when measuring ride height, as they often vary by make and model. This example is from a 5th-generation Ford Explorer. Ford wants you to first measure the distance between the flat level surface and the center of the lower arm ball joint cap (measurement 2). Then measure the distance between the flat level surface and the center of the lower arm inboard bolt (measurement 3). Finally, subtract measurement 3 from measurement 2 to get the desired number.
BY FORD MOTOR COMPANY
vehicles in adjacent lanes as potential obstacles when they are not
In short, failure to reset the SAS can cause the ADAS system to believe the vehicle is turning when it’s not. After every alignment, the SAS should be recalibrated, a simple step but one that is often overlooked.
It’s also worth remembering that the vehicle will cross-check SAS data with that from yaw rate sensors and longitudinal accelerometers. If data from the SAS says the car is turning, but the yaw rate sensor doesn’t detect rotation, the system knows something is incorrect. This will often lead to calibration faults or stability control warnings.
Alignment and Calibration
Workflow: Best Practices for ADAS-Equipped Vehicles
Every manufacturer will outline their preferred workflow for ADAS-equipped vehicles, but one thing is for certain. ADAS calibration and wheel alignment must be thought of as one singular service. They should not exist inde -
pendently. We have seen the shift with leading tool and equipment manufacturers combining ADAS and wheel alignment equipment for this very reason.
While OEM-specific variations exist, a general six-step best practice applies to most late-model ADAS-equipped vehicles:
Pre-Scan Documentation. Before any mechanical work begins, connect a diagnostic tool and perform a full system scan. Record any existing DTCs, freezeframe data, and calibration information. Keep an eye out for historical or inactive ADAS-related faults; they can provide clues about prior calibration attempts. Many scan tools will compile prescans into easily shareable reports, and that leads to the next point: document everything. Keep a record of everything from battery voltage to ride height measurements. A printed or saved report establishes a baseline and protects the shop if issues arise later.
Suspension Inspection. Before you start the alignment, measure and verify ride height against OEM specifications. Make note that you are following OEM ride height measuring procedures as well
as thoroughly and correctly inspecting suspension and steering components. Remember, you can’t align looseness!
• Verify tire size and inflation pressures
• Note tire conditions and abnormal wear patterns
• Make sure that vehicles with air or adaptive suspension systems are in the correct ride mode for the alignment to take place
Perform a Precision Four-Wheel
Alignment. Again, documentation. Always print or save the alignment report; you’ll often need it to explain results or validate work.
Steering Angle Sensor Reset. Once the alignment is complete, perform an SAS reset or calibration in accordance with the OEM procedures. This step ensures that what the vehicle believes “straight ahead” is matches the vehicle’s geometric thrust line.
ADAS Calibration. Whether dynamic
or static, now that the chassis geometry is verified, you can perform the ADAS calibration.
• Static calibration requires precise target placement, with a level floor, correct lighting, and correct free space
• Dynamic calibrations rely on favorable road conditions and can fail if those conditions are not met.
Post-Scan and Verification Road
Test. After the calibration is complete, perform a post-scan to validate the calibration and then perform a road test to verify system functionality.
Closing the Loop Between Geometry and Technology
As vehicles become more dependent on ADAS technology, alignment has evolved from a basic maintenance task to a precision prerequisite for safety. Every sensor, radar, and camera assumes the vehicle’s geometry is correct. If it isn’t, every decision those systems make will be built on error. Proper alignment, verified ride height, and accurate calibrations are the foundation of system integrity. When alignment and calibration are approached as one connected process, technicians can deliver vehicles that truly perform as designed. Safe, accurate, and ready for the road ahead.
ERIK SCREEDEN serves as technical and multimedia content director for Motor Age. An ASE Master Technician with L1 and L4 credentials, he brings more than 25 years of industry experience. Screeden began his career as a Ford dealership technician, later working at independent repair facilities and a GM-specific performance shop. He transitioned to diagnostic and J2534 tool support before finally leveraging his expertise in technical sales.
BECAUSE ADAS is so interdependent on accurate wheel alignment, equipment manufacturers like Hunter Engineering Company and their Ultimate ADAS system now facilitate wheel alignment and static ADAS calibration with the same equipment. This helps ensure error-free and accurate calibrations.
PHOTO BY HUNTER ENGINEERING
WITH SO many modules on vehicles, it’s extremely important to do an all-system DTC scan before attempting any type of ADAS calibration. Just because there isn’t a warning light or a dash message doesn’t mean there isn’t something lurking in the vehicle history that can lead to problems down the road.
PHOTO BY ERIK SCREEDEN
Installing a LS Crankshaft Reluctor Wheel
A step-by-step guide to correctly positioning the reluctor wheel for precise timing
BY MIKE MAVRIGIAN // Editor
AN EXAMPLE of a crankshaft that was purchased without a tone wheel. Depending on the crankshaft manufacturer, crankshafts are available without a tone wheel or with a wheel pre-installed.
PHOTO BY MIKE MAVRIGIAN
TODAY’S ENGINE COMPUTER CONTROL system monitors both camshaft and crankshaft position in order to deliver correct spark and fuel delivery. In order to accomplish monitoring crankshaft position, many crankshafts feature a press-fit toothed timing wheel, referred to as a reluctor wheel. A magnet sensor mounted stationary in the block is aligned to the wheel and picks up the crankshaft position.
To refer to one specific example, we’ll cite the GM LS engine platform’s crankshaft.
LS engines feature a toothed reluctor wheel (also often referred to as a tone wheel or tone ring), which is press-fit onto the rear of the crankshaft. This toothed wheel is used by the crankshaft position sensor for ignition timing. There are two styles of wheels. The Gen III LS1/ LS6/LQ4 engines originally used the 24tooth reluctor wheel, while the Gen IV LS2/LS7/LS3/LS9 engines featured a 58-tooth wheel. In most cases, you can identify a Gen III or Gen IV by the location of the camshaft sensor. Gen III engines featured the cam sensor mounted at the top rear of the block, while Gen IV engines feature the cam sensor mounted onto the timing cover.
Either tooth-count wheel can be installed on any LS crank, as long as you have a controller designed for the specific tooth-count. If you’re starting from scratch and have a choice, it’s best to go with a 58-tooth wheel and matching controller for a more accurate timing control. The reluctor wheel may require removal/replacement for a variety of reasons—the wheel may be damaged, or the crankshaft needs repair, and the wheel must be removed to perform journal resurfacing, or a new crankshaft must be installed that did not come with a reluctor wheel.
If you plan to maintain the OE original controller/engine management computer, you’ll need to stick with the same version (24 or 58 tooth) of wheel that the engine’s
controller originally used. If you plan to use an aftermarket controller, it really doesn’t matter, as long as you buy the correct timing controller that matches your wheel’s number of teeth.
Basically, the OE LS cranks are identical and will install in all LS blocks (variances exist in terms of stroke, and engines that were originally fitted with dry-sump oil systems will feature a longer snout). Regardless, one of the features common to all is the need for a toothed reluctor wheel.
Whether you plan to reuse the OE crankshaft that was included in your new or used engine, or if you plan to install an aftermarket performance crankshaft, you may run into a situation where the reluctor wheel must be serviced. As noted earlier, perhaps the original tone wheel is damaged (teeth missing or bent), or maybe you have a crank with a 24-tooth wheel, and you want to switch to a 58tooth wheel, or possibly a new crank that you bought does not include an already-installed wheel. Most aftermarket
crank makers will sell their LS cranks with the wheel already installed, but you can run into a situation where the wheel is sold separately.
Here we’ll explain the procedure involved in installing a reluctor wheel. It’s not a simple matter of hammering the wheel onto the rear of the crank. The tone wheel must be indexed correctly to the crank. If not timed correctly relative to the crank’s rod throws, the engine either won’t fire at all or it will run severely out of time.
Removing/Installing the Reluctor Wheel
The reluctor wheel (also referred to as a timing wheel or tone wheel) is interference-fit onto the rear of the crankshaft, with no key or other registering device. If you’ve removed the tone wheel from a production crank, or if you’re faced with installing a new tone wheel onto a new crankshaft, where the two components were purchased separately, it’s critical to understand how the wheel is to be installed.
the reluctor wheel already installed. The wheel (also called a tone wheel or tone ring) features a series of teeth that travel past a block-mounted crank position sensor, providing crankshaft position signals to the ECU.
PHOTO BY MIKE MAVRIGIAN
TONE WHEEL clock position and method of installation is critical. Don’t attempt it if you don’t know what you’re doing, as you can easily ruin the wheel.
PHOTO BY MIKE MAVRIGIAN
SHOWN HERE is a new crankshaft with
WHEELS are available in both 24 tooth (LS1/LS6 versions) and 58 tooth (Gen IV/LS2, LS3, LS7, etc.). Selecting the tooth count all depends on your ECU (if you plan to use an OE harness and computer) or an aftermarket timing control module. The two need to match; if you have a 24-tooth wheel, you need a controller for a 24-tooth wheel. The same goes for the 58-tooth wheel (where you’d need a 58-tooth controller). If you already have a controller, then you need to buy the correct tone wheel to match that controller.
Removing an Original Tone Wheel
If an original tone wheel is to be removed, first place matchmarks on both the tone wheel and crank rear flange. Again, the position of the wheel is critical.
Do not attempt to remove the wheel with a puller, since you’ll bend/distort the relatively thin wheel. Instead, carefully and evenly heat the wheel with a torch to roughly 200 F. As the wheel expands as a result of heat, it can easily be pulled off by hand (obviously, you’ll need to wear heavy welder’s gloves). This can also be done in a cleaning oven (assuming an oven is available).
The reluctor wheel features a series of teeth that provide crankshaft position signals (via a sensor) to the ECM. The wheel interference-fits to the rear of the crank, immediately forward of the No. 5 main bearing. Typically, the wheel features about a 0.007” interference fit.
The Indexing Dilemma
Since LS cranks feature no keyway or other index point, how do you know where to locate the wheel? Luckily, aftermarket indexing tools are available, such as the unit developed by Goodson Shop Supplies that we’re featuring in this article. They offer a very handy and absolutely essential indexing and installation tool for LS reluctor wheel mounting.
The RRJ-350 Reluctor Ring Jig is comprised of a short steel tube that’s equipped with two indexing pins. An external tang
THE SPECIALLY-DESIGNED installer tool is necessary for tone wheel installation, as it precisely indexes to the 8mm hole in the tone wheel.
PHOTO BY MIKE MAVRIGIAN
GOODSON’S RELUCTOR wheel installation tool (Goodson refers to this as their RRJ350 Reluctor Ring Jig) enables you to accurately locate and install the tone wheel.
PHOTO BY MIKE MAVRIGIAN
THE JIG tool’s 8mm locating dowel is shown here. This dowel engages the tone wheel and is located on a welded tang on the outside of the tool body.
PHOTO BY MIKE MAVRIGIAN
TONE
PHOTO BY MIKE MAVRIGIAN
AN LS reluctor wheel typically features an interference fit of about 0.007” onto the smooth outer surface of the crankshaft’s rear flange. The crank flange must be clean and free of burrs. Do not attempt to cheat by grinding material from either the crank flange or the inside edge of the tone wheel’s center hole.
PHOTO BY MIKE MAVRIGIAN
THE INSTALLATION tool’s internal dowel engages the crankshaft’s rear flange dowel hole.
PHOTO BY MIKE MAVRIGIAN
secures a threaded stud, with the stud tip turned down to 8 mm. This pin engages in the single 8 mm indexing hole in the reluctor wheel. An internal guide pin (a threaded stud with the tip turned down to 11 mm) engages into the 11 mm blind dowel hole in the crank’s flywheel flange. This jig orients the reluctor wheel precisely in the correct timing position. The two dowel studs feature jam nuts to allow depth adjustment (you simply want to make sure that the 8 mm dowel passes through the wheel’s 8 mm hole, and that the 11 mm dowel projects out far enough to engage the crank flange dowel hole).
Installation Procedure
For purposes of this article, I performed a sample installation. First, I lightly chamfered the entry hole of the reluctor wheel, and lightly chamfered the edge of the crank’s reluctor wheel flange. Goodson’s instructions advise this chamfering to ease installation.
The instructions also state that the wheel may be pressed onto the crank or heated to 450 F for a slip-on fit. Attempting to cold-press the wheel onto the crank can be tricky since maintaining a square alignment of the wheel to the crank may be difficult. Pre-heating the wheel (resulting in the center hole expanding) makes the job easier and much more controllable for a precise indexing fit.
In our example, I heated the reluctor wheel’s I.D. lip with a torch and slipped the wheel onto the Goodson jig. This allowed me to smoothly slide the wheel onto the crankshaft.
You’ll definitely need to install the ring by pre-heating it, instead of potentially ruining the ring by cold pressing. Pressing, if not done with a high degree of precision and care, can easily warp the reluctor wheel, rendering it useless. Do not try to force the wheel onto the crank by striking it with a hammer. That’s a guaranteed way to ruin the wheel.
( Caution: The tone ring is made of two plates riveted together. If you are
A CLOSE-UP view of the tone wheel’s indexing hole.
PHOTO BY MIKE MAVRIGIAN
THE TONE wheel is positioned on the crankshaft with the two “arrowhead-shaped” holes at 90 degrees to the number 1/2 rod pin, with the series of large holes in the wheel positioned opposite the first rod pin. That’s only a rough description. Do not attempt to install a tone wheel by eyesight. It is critical to use the proper installation tool.
PHOTO BY MIKE MAVRIGIAN
HERE WE see the installer tool’s outer dowel pin engaged into the tone wheel’s 8mm indexing hole.
PHOTO BY MIKE MAVRIGIAN
WITH THE tone wheel heated and installed on the tool, the tool and tone wheel, as an assembly, will easily slip onto the crank flange. Do not strike the tool or the tone wheel with a hammer. Heating the wheel can be accomplished in a convection oven or by careful use of a torch.
PHOTO BY MIKE MAVRIGIAN
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using a press, and if you cock it out of alignment and continue to press, the plates can begin to separate. If this happens, you can pinch the plates together with C-clamps and carefully tack-weld it back together at the rivet hole locations. Just be careful to avoid creating a warp/ runout condition.)
Since this special jig indexes to both the wheel and to the crank, misalignment is avoided. If you expect to service LS engines, I highly recommend buying this jig. It takes all of the guesswork and time-consuming measuring out of the equation. Don’t even try to press it on cold. Simply heat the ring, seat it onto the jig, and place the jig and wheel onto the crank. With heat and the right tool, it’s easy.
Final Inspection
Once the wheel has been installed and allowed to cool, test-fit the crankshaft into the block and carefully inspect to verify that the wheel does not come into contact with the rear main cap area. With the crankshaft resting on the main saddles, slowly rotate the crankshaft to verify that the wheel features no discernible runout, and make sure that it is aligned with the crankshaft position sensor, which is located at the rear of the left side of the block.
MIKE MAVRIGIAN has written thousands of automotive technical magazine articles involving a variety of specialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.
NOTICE THE tight clearance of the tone wheel relative to the crankshaft counterweight and main cap. With all main bearings lubed and main caps fully installed to final torque, carefully rotate the crank to check for possible tone wheel runout. If you find more than about 0.002” runout, the tone wheel is probably bent, in which case you’ll need to replace it and start over. Do not attempt to straighten a distorted tone wheel.
PHOTO BY MIKE MAVRIGIAN
HERE’S A view of a crankshaft positioned onto the block’s upper main bearings. Notice the tone wheel at the far right in this photo.
PHOTO BY MIKE MAVRIGIAN
THIS PHOTO shows the reluctor wheel installed onto the crank, with the installer tool removed.
PHOTO BY MIKE MAVRIGIAN
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Turbo Diagnostics: How Boost, Airflow, and PCM Strategy Work Together
A structured approach to understanding sensor data, wastegate control, and system diagnostics for modern turbocharged engines
BY JEFF TAYLOR
TURBOCHARGED ENGINES are now part of everyday repair work. They show up in compact cars, crossovers, pickups, and performance models from every manufacturer. The technology is no longer reserved for a specialty corner of the shop. It’s something technicians deal with constantly, and understanding how these systems operate is essential for accurate diagnostics. A turbocharger does not look complicated at first glance. It uses the flow of exhaust gas to spin a turbine that drives a compressor, which forces more air into the engine. The goal is simple: increase the density of the intake charge so that more oxygen is available for combustion. When you increase the amount of oxygen entering the cylinders, the engine can burn more fuel and make more torque without needing a larger displacement. That basic explanation is correct, but the systems supporting a turbocharger are complex and sensitive to even minor faults.
A modern turbocharger works under extreme conditions. The turbine can spin beyond 300,000 rpm. The temperature at the turbine inlet can exceed anything else in the engine compartment. The bearings rely on a thin, stable film of clean oil. The compressor must move large volumes of air
while maintaining efficiency. The wastegate control or variable geometry system must constantly adjust to match and maintain the PCM’s desired boost pressure level.
The PCM monitors a wide range of parameters continuously, in order to deliver the correct amount of compressed air and fuel to the engine’s cylinders. When any part of this relationship drifts out of range, the effects can be immediate. The driver may feel a lack of power, illuminated MIL, poor throttle response, surging, hesitation, or a change in engine sound. A diagnostic trouble code may or may not be stored. This is why a structured approach is essential.
Sensor Rationality
A good starting point is to confirm that the engine’s intake system pressure-sensing information being fed to the PCM is accurate. Before a road test or a hands-on mechanical inspection, always begin with a rationality test. This simple check ensures that the Manifold Absolute Pressure Sensor, the Barometric Pressure Reading, the Exhaust Gas Recirculation Pressure Sensor, and any dedicated Boost/Charge Air Pressure Sensor all match each other when the key is on, and the engine is off (KOEO). You
PHOTO BY JEFF TAYLOR
want these sensors to be very close to each other during KOEO, and in most cases, the pressure difference should not be more than about 0.5 psi. If these KOEO pressure readings are not within this spec, the PCM cannot accurately figure out engine load and cannot make correct decisions about wastegate control or fuel delivery. A small error in one of these sensors can lead the PCM to believe there is an underboost or overboost condition even when boost is normal. Starting with this check prevents wasted effort later in the diagnostic routine.
Light Throttle Behavior
Once those values pass inspection, the next step is understanding how the turbocharged system behaves during normal driving. Light throttle behavior is often overlooked, yet it provides valuable information about airflow, wastegate control, and the general
THIS CUTAWAY shows the internal layout of a turbocharger, including the turbine wheel, compressor wheel, shaft, bearings, and sealing rings. The image highlights how the rotating assembly is supported by the bearing system and how the seals control oil flow while keeping exhaust and boost pressure out of the center housing. Seeing these parts exposed helps technicians understand how oil pressure, heat, and airflow work together to keep the turbo spinning freely and prevent leaks.
health of the turbocharger. During slight acceleration, the MAP value should rise above barometric pressure, and the mass airflow should increase predictably. The wastegate should begin to modulate, but should never be near full command at this stage. If the PCM is commanding the wastegate harder (higher duty cycle) than it should during low load, or if the mass airflow is weaker than expected, something is not right, because the duty cycle should stay low at light throttle and any rise in that number can point to an air leak, an airflow restriction, a sticking actuator, or a compressor problem, and this light-throttle data will reveal the issue long before it becomes dramatic.
Wide-Open Throttle and Boost Control
With that information recognized, a full-throttle road test becomes more meaningful. During wide-open throttle, the PCM commands the turbocharger to reach a specific boost target, shown on the scanner as the Desired Boost Value. When everything works correctly, the Actual Boost Value will track this commanded value closely. The gap between desired and actual boost values should remain tight; they should almost mirror each other. When the system cannot meet the commanded/desired boost pressure, the system is in an underboost condition. This condition often sets the P0299 code, which many techs are familiar with. During this underboost situation, the PCM increases the wastegate’s duty cycle command to force more exhaust energy into the turbine, spinning the compressor faster. If the wastegate duty cycle value is already near maximum and the boost stays low, the system is either leaking air (quite common), restricted, or unable to spin the turbocharger. If the wastegate command is dropping but the boost level keeps climbing past the desired value, the system is overboosting. When this happens, the PCM will set an overboost DTC, such as P0234, because it can no longer control the turbocharger, and other engine systems may become active to protect the engine from damage. The PCM can reduce spark timing,
close the electronic throttle, limit fuel delivery, shut off boost control, or place the engine in a reduced power mode to keep cylinder pressures from climbing too high during an overboost event. These patterns reveal most turbocharger faults before any mechanical work is done.
Wastegate Function and Control Methods
Wastegate function is central to boost control. Each manufacturer does it a little differently, but the idea is always the same. The wastegate manages how much exhaust energy is allowed to drive the turbine. At idle, the wastegate stays closed so the turbo is ready to respond, and as load increases, the PCM moves it as needed to hold the commanded boost. This keeps the system from falling into underboost or climbing into overboost. If the wastegate hangs open, too much exhaust bypasses the turbine, and the turbo will spool slowly with low boost output. A wastegate that is stuck closed can easily cause an overboost condition, which can trigger engine protection mode if equipped and limit engine power.
Many manufacturers still use vacuum-actuated wastegates. These systems introduce another potential failure point because the vacuum supply must be strong and consistent. A weak vacuum pump, a restricted line, a leaking vacuum reservoir, or a leaking control valve can limit wastegate movement. This results in the wastegate appearing functional, but it may not be able to travel far enough to control boost effectively. Understanding the relationship between command, position, and vacuum supply is important in these systems. A pressure-actuated wastegate relies on boost pressure fed directly to the actuator to control how far the wastegate opens. Any leak in this hose or control path will change the pressure the actuator sees and can cause the wastegate to open too early, too late, or not at all.
Some engines use electric wastegate actuators. These units provide precise control and faster response and are often found on smaller displacement turbocharged
engines where accuracy matters. Electric actuators require proper calibration after replacement, and many manufacturers include a dedicated adaptation or relearn procedure. Skipping this step is a common cause of repeated underboost or overboost complaints. Manufacturers such as BMW, Volkswagen, Audi, Hyundai, and Stellantis all need specific wastegate calibrations after service. Many electric turbo wastegate
A CLOSE-UP of the turbine wheel and the internal wastegate. The wastegate controls how much exhaust reaches the turbine, and any sticking or wear here will affect boost and spool speed.
PHOTO BY JEFF TAYLOR
THIS IMAGE shows the wastegate linkage on a Ford Focus turbocharger. Wear or looseness at this joint can cause boost control issues and inconsistent wastegate movement.
PHOTO BY JEFF TAYLOR
DETAILED LOOK at a broken wastegate linkage clip; a quick visual inspection often catches these mechanical faults before deeper diagnostics begin.
PHOTO BY JEFF TAYLOR
actuators will run a self-test during engine shutdown, and the technician can often see the learned positions and commanded values change as the actuator sweeps through its calibrated range.
Another major design is the variable geometry turbocharger. This is common on diesel engines and is starting to appear on
BY JEFF TAYLOR
some gasoline applications. A Variable Geometry Turbocharger uses a ring of movable vanes to change the flow characteristics of the exhaust entering the turbine housing. At low speeds, the vanes close in, which accelerates the exhaust and helps the turbocharger spool quickly. At higher loads, the vanes open, allowing more exhaust flow while preventing excessive backpressure. The advantage is strong low-end torque and smooth power delivery. The challenge is that the mechanism is sensitive to soot accumulation, corrosion, and mechanical wear. When the vanes cannot move freely, the turbocharger becomes slow to respond or cannot reach the desired boost. Manufacturers such as Ram, Ford, and GM have specific actuator relearn routines after VGT turbocharger or actuator replacement or cleaning. These procedures ensure that the PCM understands the fully open and fully closed positions of the vanes. A technician must always perform these calibrations, or the turbocharger will not operate
correctly. Like the non-VGT design, the VGT wastegate will perform the same calibration tests when the engine is shut off, sweeping through its range so the PCM can confirm the learned positions.
Oil Supply: The Lifeblood of Turbocharger Health
A steady, clean, filtered oil supply is one of the most important factors in turbocharger life. The turboshaft that connects the turbine and compressor assemblies rides on a very thin film of oil. In a fully-floating bearing system, the oil forms a wedge that suspends the shaft and prevents metal-to-metal contact. Because the turbocharger’s rotational speeds are so high, any interruption or contamination in the pressurized oil supply can potentially damage the bearing surfaces. Restricted oil feed lines, contaminated oil, clogged filters, and coked oil passages all contribute to turbocharger failure. Many modern turbochargers include narrow-feed passages that are easily restricted when oil quality drops. Some manufacturers specify
data compares full boost and bypass modes. At wide open throttle, the bypass stays closed, and airflow rises sharply, while at part throttle the bypass opens and airflow drops, showing normal turbo control.
the MAP, BARO, and
reading within about 3 kPa of each other with the key on and the engine off. Matching values here confirms the sensors are aligned, and the system is ready for accurate boost control.
THIS COMPARISON highlights the hot exhaust side and the cold intake side of the turbocharger. Understanding the temperature difference between these sections helps explain why heat management, oil supply, and proper airflow are critical to turbocharger life.
PHOTO
THIS DIAGRAM shows the exhaust, intake, and crankcase pressure areas that surround the turbocharger. Any leak or restriction in these zones will change the pressure balance across the seals and can lead to oil leaks, poor spool, or boost loss.
PHOTO BY JEFF TAYLOR
A CLOSER look shows a turbocharger seal ring covered in carbon and oil residue.
PHOTO BY JEFF TAYLOR
THIS IMAGE shows a close-up of a clean turbo seal ring. These rings work like piston rings, using pressure in the system to help keep oil inside the center housing and prevent boost or exhaust gases from leaking across the shaft.
PHOTO BY JEFF TAYLOR
THIS SCAN data shows
boost sensors
PHOTO BY JEFF TAYLOR HOT COLD
THIS SCAN
PHOTO BY JEFF TAYLOR
replacing the oil feed line during turbo service to prevent contaminants from entering a new turbocharger. BMW, Volkswagen, Audi, and some GM and Ford applications include this requirement.
A turbocharger’s compressor wheel can feel slightly loose when the engine is off because the bearings are not supported by oil pressure, and this small amount of movement is normal and not usually a concern. Once the engine is running, the pressurized oil lifts and centers the rotating assembly, taking up that clearance and allowing the turbo to spin smoothly at high speed.
Oil Leakage and Pressure Balance
Oil leakage is another area of confusion. Many technicians assume that oil found in the compressor housing or the turbine housing indicates a failed turbocharger. Turbochargers rely on dynamic sealing and pressure differentials, and don’t use traditional oil seals. Turbo seals function similarly to piston rings, employing precisely matched metal rings to contain the lubricating oil. They depend on pressure differentials within the turbocharger to retain oil within the bearing housing while preventing the boost pressure and exhaust gases from entering. The pressure in the compressor housing, turbine housing, and center housing must remain balanced. If the crankcase ventilation system becomes restricted or if the intake system has a blockage, the pressure can shift, and oil will move to an area where it normally does not belong. A restricted air filter, a blocked drain tube, a collapsed intake duct, or a sticking variable geometry mechanism can all create pressure imbalances. Replacing a turbocharger without diagnosing the pressure imbalance will result in another failure. Oil control must be viewed as part of the system rather than a fault separated from airflow and pressure.
Bypass and Diverter Valve Control
Airflow management continues with the bypass or diverter valve. When the throttle closes during boost, the pressure trapped between the turbocharger and the throttle
plate must be relieved. If it is not relieved, the turbocharger may stall briefly as the airflow reverses direction. This causes noise, surging, hesitation, and in worst case scenario, turbocharger damage. The
bypass valve either vents or recirculates this trapped pressurized air. When it leaks or reacts slowly, the engine may struggle to reach commanded boost or might surge when the throttle is lifted. Data logging helps here because the mass airflow and manifold pressure drop sharply when the bypass valve activates. The technician can compare throttle position, bypass valve command, and airflow change to see whether the system is reacting correctly. GM, Ford, and many European manufacturers rely heavily on electronically controlled bypass valves. These units fail in subtle ways and often require scan tool monitoring rather than simple visual inspection.
The Intercooler: Managing Charge Air Temperature
The intercooler or Charge Air Cooler is another part of the system that affects overall performance. Compressed air generates significant heat. Hot air contains fewer oxygen molecules, so cooling the compressed air charge increases power. Air-to-air intercoolers use ambient airflow and are common on lighter vehicles. They can crack at the plastic end tanks or leak at couplers. Air-to-water
intercoolers provide consistent cooling and are common on performance engines, but add more components that can fail. Some engines are known for specific intercooler issues. Ford engines can accumulate moisture inside the intercooler under humid conditions. GM has dealt with intercooler icing in cold climates, and newer models now have dedicated data PIDs that can help diagnose a frozen intercooler. VW diesels have suffered from the same frozen CAC issues. Diesel engines can develop cracked plastic intercooler end tanks because of the heavy demand placed on the system, and knowing this pattern helps the technician avoid confusing a simple airflow loss with a fuel or ignition concern.
PCM Resets and Learned Values
PHOTO BY JEFF TAYLOR
Many modern turbocharger repairs also require specific PCM resets or learned value procedures to make sure the system operates the way it was designed. Many manufacturers store adaptive airflow and boost control data. After repairing an intake leak, replacing a turbocharger, servicing a wastegate actuator, or replacing a sensor, these learned values must be cleared. GM requires an Intake System Learned Values Reset after certain turbocharger repairs. Ford often requires a PCM relearn after intake or boost control service, and this often includes BARO sensor value resets. Volkswagen and Audi require a turbocharger adaptation routine that sets the wastegate and boost control positions. BMW systems often need a wastegate adaptation and, in some cases, PCM coding after turbocharger work, and skipping these steps can bring false underboost or overboost faults right back. Following the manufacturer’s procedure keeps the boost system under control and helps avoid repeat faults, which protects both the repair and the customer’s trust. When these steps are completed properly, the turbocharger can deliver the performance and efficiency it was built to provide.
A Structured Diagnostic Approach
Turbochargers stay reliable when the sys-
tems around them are healthy and when the technician works through the diagnosis in a steady and organized way. When you understand how airflow, pressure, oil supply, mechanical parts, and PCM strategy fit together, the entire diagnostic process becomes much easier.
A technician who follows a structured approach can find turbocharger faults quickly and with confidence. Start by confirming sensor rationality, then study light throttle and wide-open throttle data, check wastegate operation, perform a proper boost leak test using the correct tools so the system can be brought up to the right pressure, verify oil supply and pressure balance, consider intercooler performance, and finish the repair with all required adaptations.
Turbochargers are here to stay. They help manufacturers meet emissions and performance targets without increasing engine size. They reward the driver with strong torque and good fuel economy. When technicians understand how all the components work together, turbocharger diagnostics become straightforward. The system behaves predictably when it is healthy. The key is knowing how to recognize when one part of that system has moved out of its expected range and then correcting it properly. With the right approach, technicians can keep these engines performing the way they were designed and prevent early turbocharger failures.
is a seasoned professional at CARS Inc. in Oshawa with 40 years in the automotive industry. As a skilled technical writer and training developer, he holds licenses in both automotive and heavy-duty vehicle repair. Jeff excels in TAC support, technical training, troubleshooting, and shaping the future of automotive expertise.
JEFF TAYLOR
THIS SCAN data shows three intake air temperature sensors used to track temperature changes through the air path. Some GM systems may infer IAT values, so always confirm sensor locations and wiring before diagnosing temperature faults.
THESE SCAN readings show the icing checks used on late-model GM turbo engines. Both the Canyon and Terrain monitor charge air cooler temperature and airflow changes to detect icing that can cause sudden underboost.
PHOTO BY JEFF TAYLOR
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Demand the Gold Label. Trust
and Clamping Force
BY NOAH NELSON
‘GOOD ‘N’ TIGHT’ IS A PHRASE THAT COSTS repair shops millions in comebacks. It’s a mentality from a bygone era, and in the modern world of mixed-material engines, it’s a direct route to warped components and client dissatisfaction. The ‘tight enough’ mentality is a fundamental misunderstanding of the purpose of a fastener. The fastener doesn’t just make things ‘tight’; it provides specific forces to accomplish a task. This involves two key forces:
• Preload. The tension, or stretch, created in a bolt as it is tightened.
• Clamping Force. The equal and opposite force applied to two surfaces, created by the bolt’s tension.
As technicians, we must deliver those forces precisely to ensure a quality repair—forces we cannot feel but must measure. Our hands and arms sense overall resistance but cannot distinguish between the friction of the fastener and the effort to stretch the bolt.
The 90/10 Friction Problem
One critical factor to consider is the 90/10 rule. Approximately 90% of the torque applied to a given fastener is used only to overcome friction. The remaining 10% does the actual work of stretching the fastener to apply the correct preload and clamping force for the situation. Without measurement, you are only able to feel the 90% and are guessing at the 10%. Any minor change in friction (such as a bit of rust in the threads or oil on a fastener specified as “dry”) has a significant impact on the final 10%, guaranteeing a failed torque.
A Modern-Day Disaster: Mixed Materials and Human Error
Another consideration is the use of mixed materials in modern vehicles. We’re dealing with plastic valve covers on aluminum heads and a cast iron block with rubber and MLS gaskets. The use of lightweight materials in parts has a significant impact on the clamping force. These parts need an even, repeatable clamping force applied to the entire surface area.
Unlike forgiving cast iron, these lightweight aluminum and plastic components will warp if the clamping force is uneven, which can lead to a leak. Relying on perception over calibrated tools is often a matter of guesswork, resulting in poor outcomes. ‘Tight enough’ at the start of the week rarely matches ‘tight enough’ after days of fatigue. The feel of a fastener in one position can be different than the feel
of a fastener that is in a different position or at an awkward angle. A 1/4-inch ratchet will feel different than a 1/2-inch ratchet. A precisely calibrated digital torque wrench is repeatable and measurable.
In a modern repair facility, clients expect repairs to be done right the first time. Consistently following torque specifications and sequences not only prevents costly rework but also ensures peace of mind for both technicians and clients. The key is to prioritize accuracy in every repair to maintain trust and efficiency.
The Pro’s Guide: From “Feel” to “Fact”
Now that we understand the fallacy, how do we move from “feel” to a professional, repeatable process? It comes down to actively controlling the variables that good ‘n’ tight ignores.
1. Control Friction: The “Wet vs. Dry” Factor Since friction is the 90% variable, it is the first and most critical one that a technician must control. Every torque specification is engineered for a specific coefficient of friction. This means the engineer’s calculation assumes the threads are either “dry” or “wet” with a specific lubricant.
SETTA SORNNOI / SHUTTERSTOCK
REFORM, DON’T Cut. Use a thread chaser (left) to reform threads. Cutting taps (right) remove critical material, weakening the joint and compromising the torque calculation. PHOTO BY NOAH NELSON
CONTRIBUTED PHOTO
• Disaster Scenario 1 (Over-torque). A technician sees a “dry” spec but decides to apply a small amount of anti-seize or oil to the bolt to “help it.” The friction plummets. When the wrench clicks at 80 ft-lbs, that 10% of “stretch” is now 40% or 50%. This yields the bolt, strips the threads, or, in the worst-case scenario, cracks the component.
• Disaster Scenario 2 (Under-torque). A “wet” spec calls for bolts to be dipped
6.
Tighten cylinder head bolts (4) in sequence
1. First Pass tighten to 80Nm (59 lb ft)
2. Second pass tighten + 90°
3. Final pass tighten + 60°
results displayed as red, green or yellow for caution
• Tests 7 different 12 volt relays
• Improved & more effective test finds intermittently bad relays
in 30-weight oil. Tech installs them dry to avoid a mess. Friction spikes. The 80 ft-lbs “click” is achieved, but 99% of that torque was lost to friction. Almost no preload is achieved. This guarantees a leak or a loosened fastener down the road.
The Pro’s Process. Always start by cleaning threads with a thread chaser (which reforms threads, not a tap, which
7. Tighten cylinder head bolt (3) in sequence
1. First Pass tighten to 80Nm (59 lb ft)
2. Second pass tighten + 90°
3. Final pass tighten + 40°
cuts new material). Visually inspect the threads for damage. Then, apply the exact lubrication specified by the OEM, or install the fastener perfectly clean and dry, as the procedure dictates.
2. Control the Tool:
The Calibration Factor
With the friction variable controlled, the next step is to ensure the tool itself is correct. A torque wrench is a measuring instrument, not just a ratchet. Using an uncalibrated torque wrench is just a more expensive way of guessing. All types of wrenches—beam, click, and digital— drift over time. Click-type wrenches are especially sensitive. Dropping one on the floor or storing it with the spring under tension (i.e., not wound back to its resting position) can create an immediate error. Your torque wrench must undergo regular calibration (at least annually, or as per your shop’s quality-control policy). Always store click-type wrenches at their lowest setting to relax the spring.
3. Control the Method: Why TTA is King Finally, engineers are fully aware of the friction problem. Their solution, which is now standard on most modern engines, is the Torque-to-Angle method. It is designed specifically to eliminate the friction variable
The TTA process is simple:
• Seating Torque. A low initial torque (e.g., 25 ft-lbs) is applied. This snugly secures the components and aligns all fasteners to a uniform, friction-overcoming starting line.
• Angle of Rotation. A specific degree of rotation (e.g., “plus 90 degrees”) is then applied.
This method is superior because once the fastener is seated, the angle of rotation has a direct, physical relationship with the bolt’s pitch and stretch. Turning that bolt 90 degrees will stretch it by a highly predictable
amount, regardless of whether the threads are slightly oily or slightly dry. It takes the guesswork out. This TTA method is often paired with Torque-to-Yield bolts. These fasteners are designed to provide a uniquely high and consistent clamping force by being stretched once into their “plastic” (yield) zone. This permanent stretch is precisely why they are single-use. Reusing a TTY bolt guarantees poor clamping; it’s permanently stretched and can’t be secured again.
The Pro’s Process. Always have the right tools before you start the job. If a procedure specifies TTA, a simple torque wrench is insufficient—you must have an angle gauge or a digital torque-angle wrench. If the procedure calls for TTY bolts, you must have a new set on hand. Attempting the job without the correct, specified fasteners and tools is no different than guessing.
From ‘Tight’ to ‘Correct’
At the end of the day, we have a duty to our clients to repair their vehicles professionally and without comebacks. Relying on feeling alone for tightening is focusing on input and ignoring the outcome. We owe it to ourselves and our clients to ensure the outcome is a securely fastened part and a reliable repair. Stop guessing and start knowing.
NELSON serves as technical editor for Motor Age. He started his 20-plus-year career as a lube technician and evolved through the ranks into district management. Now an ASE Master Technician, Noah leverages his diverse background to
PHOTO BY NOAH NELSON
Deny It at Your Peril:
WHAT 50 YEARS OF EMISSIONS SCIENCE HAS TAUGHT US
BY CRAIG VAN BATENBURG
ABOUT 20 YEARS AGO, I was teaching a hybrid class at a large automotive convention and was asked if pure electric cars were the future. My answer uncovered a division in the automotive repair world. We know more now than we did then in 2006. Let’s get up to date.
Like you, I have been referred to as a mechanic until they called me a technician in the late 1970s, since I received a
paycheck working on internal combustion-powered vehicles in high school. To understand the future, we must study the past.
My grandfather, Ed Finacom, was born in 1892 in Washington, D.C., and worked as a mechanic after school. In 1900, 33,842 electric cars were sold in the United States, making them the most popular vehicle type and accounting for 38% of all auto-
mobiles on the road. These electric cars were favored over gasoline cars for being quieter, cleaner, and easier to operate, as they didn’t require a hand-crank to start. Electric cars were particularly popular in Washington, D.C. Ed was exposed to internal combustion in the following years. After high school, he moved to Worcester, Massachusetts, to take a job at the electric company, eventually becoming the shop
JÜRGEN WACKENHUT / ADOBE STOCK
foreman at Mass Electric. His daughter, Shirley, married a mechanic, Raymond, from Ogden, Utah, and he opened a used car lot after World War II. At age 12, my parents divorced, and we moved from Utah to Worcester, without my dad.
Like many of the technicians I have known over the years, their path into the repair industry has a story. Few of them followed the “college upon graduating from high school” route. I am no exception. Science and chemistry, plus my auto shop class, were subjects I gravitated toward. Little did I know this education would help my long-term career.
Fast forward to 1999. The Automotive Career Development Center opened Oct. 1 as one of many Massachusetts-certified emissions training facilities. Fifteen days later, I paid my deposit to Lundgren Honda to be first in line for a new Insight, the first hybrid offered for sale in America. As I drove my new hybrid and started training technicians in my local area, the education I had lacked was supplemented by Aspire, a training program located near Philadelphia, a few years earlier. It was good stuff. Massachusetts started testing vehicle emissions in 1983, making it one of the first states in the country to do so. Massachusetts has the highest percentage of adults with bachelor’s degrees or higher in the nation. Around 44% of adults have a bachelor’s degree, and approximately 32% have a graduate or professional degree. That is 76%. The high school graduation rate is also high, at over 96%. I have a high school diploma. I must have brought that average down a bit. They say people here are “wicked smart”; now you know why. Love the accent.
We can all agree that a top-notch technician must have above-average intelligence to understand the complex systems we work on. What about formal education?
We must include the Honda company and Soichiro Honda, the founder, in this article. He was clear with his engineers: to fix any problem with his vehicles, go to the root
cause. They did in model year 1975 with the Compound Vortex Controlled Combustion design. The fuel was burned at a lower temperature and at a slower rate. A catalytic converter was not needed until 1981 in most states. Good engineering, chemistry, and not making pollution to begin with were Honda’s strengths. I was in my 20s and soaking up technology like a sponge.
5-Gas Training
Without getting into complex molecular formulas, your 5-gas analysis training most likely started—depending on your age and where you worked—when your shop had to fix a “failed emissions” related repair. Many well-populated areas of our country set up inspection stations, often including safety measures, to test the tailpipe gases of vehicles using gasoline. If you have never worked in an “emission-regulated area,” there are still books and videos to get you there.
The five gases tested on an internal combustion engine’s exhaust are carbon monoxide (CO), carbon dioxide (CO₂), hydrocarbons (HC), oxygen (O₂), and nitrogen oxides (NOx). A 5-gas analyzer is used to measure these gases, which helps diagnose air/fuel ratio problems, combustion issues, and other engine malfunctions to ensure the vehicle meets emissions standards.
• Carbon monoxide is a deadly gas produced from incomplete combustion caused by a rich mixture.
• Carbon dioxide is a product of complete combustion.
• Hydrocarbons are unburned fuel particles that react with sunlight to cause photochemical smog.
• Oxygen is a measure of air in the exhaust, which can indicate a lean or rich condition or an exhaust leak ahead of or near an O2 sensor.
• Nitrogen oxides are created at high combustion temperatures. NOx adds to smog.
Of the five gases, three were known pollutants: CO, HC, and NOx. Older tech-
nicians can tell stories about CO, as it would produce a severe headache if you ran older cars in the shop on a day when the garage door was closed. We all joked about “killing a few brain cells.”
What was the EPA’s Viewpoint?
Some of the information below was gathered by ACDC from the Environmental Protection Agency’s website prior to its recent removal.
This pie chart shows total U.S. greenhouse gas emissions by economic sector in 2014.
Total greenhouse gas emissions in 2014 were 6,870 million metric tons. One gallon of gasoline weighs approximately six pounds. Burning one gallon of gasoline produces about 19.6 pounds of carbon dioxide. This is due to the carbon in the gasoline combining with oxygen from the air during combustion, which increases its weight.
From the EPA’s website: “Greenhouse gases trap heat and make the planet warmer. Human activities are responsible for almost all of the increase in greenhouse gases in the atmosphere over the last 150 years. The largest source of greenhouse gas emissions from human activities in the United States is from
AN EARLY electric car in 1905. PHOTO COURTESY ST. VITAL MUSEUM
burning fossil fuels for electricity, heat, and transportation.”
This link is still available on NASA’s website: science.nasa.gov/earth/explore/ earth-indicators/carbon-dioxide/. The graph below (Fig. 4) is also from the NASA website currently. It shows an increase over time. Looks like the problem started when I was born.
Science and Chemistry
Being born way before we regulated emissions, my career has had a ringside seat in controlling pollution. Massachusetts was my petri dish.
When any gas is too high, what do we do? We follow the data presented by a scan tool and other means, but the most important tool is a 5-gas analyzer. Today, that piece of equipment is rarely used, as OBD information is faster and less expensive. My nine years as the owner and lead trainer at the ACDC, my second business, started when enhanced inspection and maintenance rules were adopted in my
state. All cars and light-duty trucks were tested on a chassis dynamometer. Our shop had a dyno installed in 1999, the same year we opened ACDC. The class was 80 hours long, one night a week. We were booked solid for years. Students would bring in their customers’ failed cars, and we would run the dyno test again to confirm the original test and put together a strategy. If we didn’t get the numbers down, we kept at it, learning as we went. Even though we had worked all day, the energy was there to fix these failed cars and get them running clean again. We all discovered that understanding the science of chemistry was the key. High CO? It needed less fuel or more air. What about an exhaust leak a few inches behind the last O₂ sensor? Problem found. Soft carbon in the combustion chamber, high HC. De-carbon the engine. Fixed. This went on for years. Logic, science, and reason were the three principles we taught. As of Oct. 1, 2008, the program shifted to “OBD-II testing only.” Tailpipe testing on a dynamometer ceased, and
5-gas testing, as a way to solve problems, went away as the equipment broke down and the companies that sold them went out of business. Today, it is a bit of a lost art. What is interesting about science is that it self-corrects. Math is a science that is never questioned. All other disciplines are subject to review. If a scientist comes up with a report that carbon dioxide warms the planet, it will be challenged. Carl Sagan was a vocal advocate for climate change awareness, testifying before Congress in 1985 about the dangers of the greenhouse effect and human impact on the climate. He used the study of other planets to explain how Earth’s atmosphere could be dangerously altered by increased greenhouse gases. Nothing serious was done. Over 50% of our oil in the 1980s was imported, and there were no other fuels for transportation available. Carl’s warnings emphasized the potential for widespread suffering, and he stressed the importance of international cooperation and taking responsibility for future generations. He was challenged by other climate scientists, as he should have been. I was in my mid-30s, running my independent Honda shop and attending college at night. My lack of education was increasingly an issue at work, so more education was needed. When I registered at Becker College in my hometown, the person behind the desk noticed my balding head and commented, “You don’t look like the average college student.” I explained why I was there, and she asked how my business was doing. As we chatted, she suggested I audit the classes. Half price, no required classes, but no degree. I needed an education, not a diploma.
It may seem hard to have two conflicting thoughts in your head at the same time, such as CO₂ traps heat in our atmosphere, and this sudden rise in global temperatures on land and in water is normal. This conflict happens when we know we have checked “everything,” but the car will not start. Case in point: When the Prius first came to America in 2000, it had no 12-volt
EXAMPLE OF a hand-held 5-gas analyzer.
PHOTO BY CRAIG VAN BATENBURG
TOTAL U.S. greenhouse gas emissions by economic sector, 2014. PHOTO COURTESY EPA
NASA SCIENCE shows the buildup of CO2 over time. For centuries, carbon dioxide levels have never been this high. PHOTO COURTESY NASA
starter motor. When the Toyota cranked over the gas engine, it did so quietly and fast. The fuel gauge was often inaccurate. Many a technician was fooled by a car they thought was idling, but in reality was still being cranked over due to a lack of fuel. It got worse if the camshaft was 180 degrees off. Once the problem was found, only then
did your opposing realities become one. The planet is overheating. Our 50 years of cleaning up the tailpipe has worked wonders. The CO is now CO₂. The HC is now CO₂ and water vapor. The NOx is now CO₂and nitrogen. If carbon dioxide wasn’t produced in such large quantities, the planet would still be about the same temperature it was 150 years ago. Sadly, the problem is real in Iowa and Utah, California and Massachusetts, the Netherlands and Zimbabwe, Australia and Brazil. This is a subject that will be debated by those in our industry who want fossil-fueled engines to stay. The rest of us will stay quiet and go about our work. The car manufacturers that build the vehicles we work on know the science. It has been about 25 years since that little Insight showed up. In America, we have over 10 million high-voltage motorcycles, cars, and even Class 8 trucks using electric
motors to add power to the wheels. What will the next 25 years bring us? What was my answer 20 years ago that created such a stir? “We have no choice. CO₂ is a problem, and we need to stop burning fossil fuels.” Deny it at your peril.
CRAIG VAN BATENBURG is the CEO of ACDC, a hybrid and plug-in training company based in Worcester, Massachusetts. ACDC has been offering high voltage classes since 2000, when the Honda Insight came to the USA. When EVs were introduced in 2011, ACDC added them to their classes. Reach Craig via email at Craig@ fixhybrid.com or call him at (508) 826-4546. Find ACDC at www.FIXHYBRID.com.
CARL SAGAN CONTRIBUTED PHOTO
TRUSTED REMAN SOLUTIONS
How shops become the hero with ETE
Every year in the United States, about 1% of vehicles will need a transmission replacement. Although an unlikely occurrence, when one is needed, it is important that the vehicle owner has a positive experience.
“When it happens, it’s scary,” said Noah Rickun, Chief Executive Officer at ETE REMAN. “The reason that ETE REMAN exists is to provide auto repair shops with a way to give vehicle owners a cost-effective and quality transmission.”
To continue supporting auto repair shops, ETE REMAN has introduced new initiatives to help owners build a more profitable and trusted business.
FASTER DELIVERY
To help increase the speed and efficiency of transmission replacements, ETE REMAN has opened several satellite warehouses across the US.
“We started with three satellite warehouses in 2025, one in Reno, Nevada; one in Dallas, Texas; and one in Orlando, Florida,” Rickun said. “We’re looking to expand in 2026, likely to the East Coast.”
Through this expansion, ETE REMAN can ship to repair shops that were once a three-to-five-day period, in one to two business days. This gives ETE REMAN customers a competitive advantage, helping them perform transmission replacements faster.
QUALITY TRANSMISSIONS
ETE REMAN dyno and leak-tests every transmission it remanufactures
REMAN
before it ships it to customers. It tests each transmission, cold and hot, and puts it through all the paces.
“Because of in-house testing, ETE REMAN can catch drivability issues and know what the transmission is going to feel like in the car,” Rickun said. “We try to do all that fine-tuning here at ETE as opposed to expecting the shops to do it themselves.”
Leak-testing and dyno-testing are one way ETE REMAN ensures repair shops experience turnkey transmission installations, reduce comebacks, and make happy customers.
UNLIMITED MILE WARRANTY
ETE REMAN transmissions come with a World’s Best, 3-Year, Unlimited-Mile warranty.
“Our philosophy is, ‘It always costs less to fix the problem than it does to not fix the problem,’” Rickun said. “In other words, the cost of an unhappy customer is far greater than the cost of just doing what’s right.”
Not only that, but ETE REMAN’s warranty requires no registration. The VIN is taken at the time of the order, and the warranty is up to five years from the date of installation. The warranty follows the transmission if the owner sells the vehicle.
ETE REMAN works with its sister company, ATSG, to provide technicians with phone support for field diagnostics and repairs. If a replacement transmission is needed, they send a unit and make the shop
whole on labor to keep everyone on track.ETE REWARDS
Another initiative ETE REMAN has rolled out is ETE REWARDS, designed to acknowledge the shop’s continuous hard work.
“We treat every customer like gold, but we do want to recognize and reward those who are doing more business with us,” Rickun said.
With ETE REWARDS, shops can accumulate points from ETE REMAN purchases and unlock rewards like discounts on purchases, gift cards, merchandise, and travel experiences. This builds on the “Switch to ETE” campaign that rewards new or returning customers with a $100 Amazon gift card with each purchase for 100 days.
MAKING LIFE EASIER
With these new initiatives, ETE REMAN has invested in ways to assist auto repair shops in being the best for their customers.
“ETE REMAN has all the repair manuals, we have all the diagnostic aids and tools, and we’ve got people here that want to help,” Rickun said. “If this is an area that you’ve shied away from in the past, I would say now’s a great time to get started.”
To learn more about ETE REMAN and its offerings, visit: BUYETE.COM.
Noah Rickun, CEO ETE REMAN
Effectively remove grime, grease, and more
The Big Wipes Heavy Duty Textured Scrub & Clean Wipes is designed to remove grease, grime, adhesices, sealants, paint, anti-seize, and dirt from hands, tools, and surfaces without the use of harsh solvents. These wipes require no water and are durable, absorbent, and safe on skin, according to the company.
Features a 250-degree swivel head
The 1/4” Drive Nano Bit Driver w/ Hex-Handle Ratchet, No. 11340, from Titan features a 250-degree swivel head, magnetic bit retention, and a minimal 4-degree sweep. The handle end functions as a magnetic bit driver, while the 90-tooth reversible ratchet allows for smooth operation. This tool is ideal for use in confined areas and on tasks that need more leverage than a finger ratchet has to offer. The knurled handle is designed for greater control. The tool is 2-1/4” long.
Features large laseretched size markings
The Matco Tools 8-pc 3/8” and 17mm Dual Drive OPTI-GRIP Star and Hex Bit Set, Nos. SB17TX8OGB and SB17XYM9OG, are designed to give automotive technicians a reliable way to tackle fasteners, even damaged ones. Patented OPTI-GRIP hex and star geometry delivers up to 50% more grip on new fasteners and up to 400% more grip on damaged fasteners versus standard tools, according to Matco, preventing rounding and improving removal success. Each S2 steel dual-drive bit measures just 27 mm long while retaining a full-length tip across most sizes for complete contact in tight engine bays. Multiple drive options include 3/8” internal square and a 17 mm external hex. Large laser-etched size markings boost visibility.
Equipped with HEAT SENSE temperature technology
The M12 Auto Shop Borescope w/ Wi-Fi File Sharing, No. 3151-21, from Milwaukee Tool delivers simplified inspections and faster repair approval.The borescope has a 5.5” HD touchscreen display and can connect to the shop’s Wi-Fi to share and document findings via email. The 5 mm access provides leverage in tight spaces, including glow plug holes and fuel injector ports. Front and side view cameras with adjustable LED brightness provide increased application viewing. High-definition photo and video with 4 times zoom allow the technician to diagnose hairline cracks. Equipped with HEAT SENSE Temperature Alert technology, if the vehicle is too hot the borescope notifies the user and shuts down. Field-replaceable 5’ camera cable for reduced downtime.
Lighten Your Load with APEX Four-Post Lift Ramps
Four-post lifts are probably the easiest style of lift to use. They’re also incredibly versatile. They provide unhampered access under and around the vehicle, are the industry standard for performing alignments, and can be equipped for brake, suspension and wheel work. They even make it possible to stack two vehicles in a single parking space.
However, while four-post lifts’ built-in approach ramps are ultra convenient and can accommodate most vehicles, they just don’t work for many sportscars, supercars, luxury sedans and lowered builds. For vehicles with low ground clearance, splitters, lips and front overhangs, traditional ramps may be too steep, making scraping a concern.
To address this challenge, shops may choose to invest in longer ramps to lower the approach angle. But many techs
hesitate to go through the hassle of taking off heavy steel ramps, dragging over slightly less heavy extended ramps, and then reversing the process when the job is done.
Now there’s a new lightweight and durable solution for easing low vehicles onto four-post lifts. APEX 48-inch four-post lift ramps are built of solid high-density expanded polystyrene (EPS) fully encapsulated in a high-performance polyurea elastomer coating to deliver smooth, stable vehicle loading while eliminating the flex, separation and premature wear common in other foam ramps.
Compared to 36-inch steel factory ramps that weigh 44 pounds apiece, APEX ramps are a full foot longer at half the weight: 22 pounds each. APEX ramps also have integrated thermoplastic handles molded directly into the body to make them easy to quickly lift, carry and position with just one hand.
APEX four-post lift ramps deliver a smooth 5.7-degree approach angle with 5 inches of lift, making them ideal not just for lowriders and performance vehicles, but also for those with standard ride heights.
These aren’t “off-the-rack” may-fit products. APEX lift ramps are engineered specifically for BendPak HD-7 and HD-9 Series four-post lifts to deliver factory-grade engagement, stability and safety. The hook nose geometry, ramp profile and pocket engagement are all matched to the ramp receivers on these BendPak models for a positive, repeatable fit.
APEX four-post lift ramps are designed for true mechanical strength. A precision-formed S-shaped insert anchors deep within the foam core, distributing load forces through the entire ramp rather than just a surface joint. The proprietary assembly is fully encapsulated in polyurea, sealing out corrosion and preventing delamination. This design eliminates loosening, separation and fatigue, even after years of heavy use.
TECHNICAL SERVICE BULLETINS
LINCOLN AVIATOR BUZZ NOISE
Some 2022 Lincoln Aviator vehicles equipped with a 3.0L EcoBoost engine and built Jan. 25, 2022, through March 10, 2022, may exhibit a buzz/rattle noise at engine idle or low RPM underneath the left rear door. This may be due to the pressurized fuel delivery line contacting the body or fuel tank.
• Remove the fuel tank.
• Clean the top of the tank with soapy water and/or isopropyl alcohol.
• Stack three Rotunda hard foam patches on top of each other.
• Install the foam patches in the area noted in the following illustration.
• Make sure that the fuel line convolute is seated in the retaining clip.
• Reinstall the fuel tank.
Photos: Mitchell 1
FORD
MUSTANG MACH-E ONE PEDAL DRIVE FAULT
Some 2021-2023 Ford Mustang Mach-E vehicles may exhibit a “1 Pedal Drive Fault—Press Brake Pedal to Reduce Speed” warning message. The 1 Pedal Drive feature may have been deactivated. DTC P0C2F:92 may also be stored in the SOBDMC. This concern may also be present when 1 Pedal Drive mode is enabled. This may be due to the SOBDMC. To correct the condition, reprogram the powertrain modules using the latest levels of the FDRS. Reprogram the PCM and check for updates for the SOBDM, BECM, SOBDMB, SOBDMC and ABS modules. (Note: Only update one module at a time.)
Photo: Ford
ALFA ROMEO COLLISION WARNING SYSTEM ALIGNMENT
This bulletin applies to 2019-2024 Alfa Romeo Giulia and Stelvio vehicles built on or before Feb. 2, 2024. The MIL may be on. One or both of the following DTCs may be set:
C1417-78 (horizontal misalignment sensor ... alignment or adjustment incorrect) C1418-78 (vertical misalignment sensor ... alignment or adjustment incorrect).
The cause involves adaptive cruise control hardware and/or software.
• Raise and support the vehicle.
• Remove the ACC module bezel/cover from the right front outer fascia grille and inspect the ACC module for a properly secured mount to the ACC bracket at the lower right pin.
• With the ACC module properly secured, perform the ACC active alignment procedure/radar calibration outlined in the service manual and clear the DTCs.
Photo: Alfa Romeo
INFORMATION COURTESY OF MITCHELL 1
