FAULT FINDER.
CHRIS ROUTLEDGE OF AUTOLOGIC DISCUSSES DIAGNOSTICS
Save time and money if you need to know why you’re losing power
Loss of power on Mercedes – all V6 diesel engines with CDI 4 injection systems
The AssistPlus system quicky diagnoses a fault and tells you how to fix it
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xperiencing a lack of power from a vehicle’s engine could be a sign of one of many issues. Finding out exactly what is causing the sudden loss of power can be a tedious job. However, using the Autologic AssistPlus system, the answer to the fault and how to fix it could take only minutes – saving you time and money. Here, we look at what to do if you experience a loss of power on a Mercedes with a V6 diesel engine and CDI 4 injection system. To repair the fault, the first step is to carry out a quick test using AssistPlus. You should find a P2510-001 or P2616 (B60) fault code. These codes point to the boost pressure regulator or signal that the exhaust back pressure is too high. It is important, however, to call Assist Technical support if you find different fault codes displayed. There are a number of possible causes for these fault codes appearing. Three likely causes are as follows: (1) the exhaust manifold flange breaking up and damaging the turbo; (2) variable vanes on the turbo seizing up or Y77/1 electronics turbo actuator faulty; (3) oil leakage.
Here’s how we repair each cause… Repair for Cause 1: Exhaust manifold breaking up The first step is to check the exhaust manifold for any damage, especially around the triangular joints, as these can break up and cause damage to the turbo itself. If there is damage to the exhaust manifold, you will need to replace it. It is important to remember that if the exhaust manifold needs replacing, then you must also replace the turbo.
check if there is a fault with the turbo actuator. You can activate it using AssistPlus by going to Y77/1 Activations: SELECT DRIVE>>ENGINE>>ACTUATIONS>> Y77/1. Now carry out the test from hot to cold. If the actuator moves, this would show the wiring and control module must be sending the correct signal to the turbo actuator. If the actuator doesn’t move, you will need to check the supply and signal line from the engine ecu, as per the Mercedes wiring diagrams. If the signal lines and supplies are good, the turbo actuator or the worm gear in the turbo actuator may be worn out. If this has happened, then you will once again need to replace the turbo.
Repair for Cause 3: Oil leakage The fault codes could also be triggered by oil leaking from the orange seal on the turbo intake and falling on to the m55 inlet port shut off motor electrical plug. This causes a short-out in the m55 inlet port shut off motor. To remedy this, you need to replace the orange seal on the turbo intake. Once this is done, you should also replace the m55 inlet port shut off motor and then check all lines and plug connections on this circuit for oil damage.
Symptoms: n Lack of power n Smoking from exhaust n Oil leaks n Whistling noise from the exhaust system n Rattling from engine bay
Fault codes: n P2510 -001. Check component Y77/1 (boost pressure regulator) positioner signals fault n P2510 -001 can also be present with P2616 (B60), which means exhaust back pressure is too high
Fault code causes: n Exhaust manifold flange breaking up and damaging the turbo n Variable vanes on the turbo seizing up or Y77/1 electronics turbo actuator faulty n Oil leakage If the faults are still present after you have taken the steps on the left, please call the Assist Technical helpline for further help on 01865 870050.
Repair for Cause 2: Variable vanes / turbo actuator fault For this cause, the first step is to
WHO IS CHRIS ROUTLEDGE?
‚ Chris is Master Technician at Autologic Diagnostics Ltd. He ll be discussing the most common vehicle faults – plus how to diagnose and fix them, fast – in Workshop Magazine every month. WorkShopMagazine.co.uk
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