What Happens When Your Audi A4 2.0 TDI EGR Valve Goes Bad? Most cars on the road today including different models of Audi come equipped with an EGR valve. For your car engine to operate smoothly, the EGR valve must be in good shape and in proper working order. Its failure can give rise to all sorts of performance issues and may even cause extensive engine damage. Luckily, there are symptoms to let you know when there is something wrong with your Audi A4 2.0 TDI EGR valve. And, in this article, we will discuss some of the most common signs that can help you diagnose and fix a faulty EGR valve before it leads to bigger problems. But first, let’s converse about the EGR valve, so you will know its basic functions.
What is an EGR valve and how does it work? EGR or exhaust gas recirculation valve is an important part of your car’s emission control system. As the name suggests, its job is to recirculate a small amount of exhaust gas back to the combustion chamber. And, by doing so, the EGR keeps the combustion chamber temperature at an optimal level and prevents the formation of oxides of nitrogen. EGR valve failure due to normal wear and tear can make your car engine run rough and emit a huge amount of NOx. Listed below are a few signs that signify that your Audi A4 EGR valve is not functioning properly.
Signs your Audi A4 EGR valve is going out Lit-up check engine light Just like any other engine-related problem, a defective EGR valve can set off your Audi A4 check engine light. The onboard computer of your car monitors different aspects of engine operation. If it finds out that the exhaust gas recirculation system is not working properly, it would activate the check engine light right away. To diagnose the issue, you need to run an OBD-II check using an OBD-II scanner. For your information, code P0401 indicates a faulty EGR valve.
Engine losing power If your Audi A4 EGR valve is not working properly, one problem you will face is acceleration loss. As you have read before, the EGR valve is employed to recirculate a portion of exhaust emissions back into the combustion chamber of the engine. If there is an issue with the valve, then an excessive amount of exhaust emissions may enter the combustion chamber, which will eventually lead to poor engine performance.
Gas mileage going down If you're getting poor gas mileage, this could be the sign of a faulty EGR valve or some other sort of engine problem that needs to be taken care of by a professional. A malfunctioning EGR valve can stuck in its open position for a very long time. And, when that happens, the temperature inside the combustion chamber may drop significantly. It would make your car engine run rough and burn more fuel than usual.
Failing emissions inspection If your Audi A4 fails an emission inspection due to high NOx emissions, this would most likely be the result of a defective EGR valve. The EGR valve is an important part of your vehicle's emission control system and is tasked with the job of minimizing NOx emissions. However, a defective EGR valve might not be able to deal with the exhaust emissions effectively, as a result of which your Audi A4 could fail the emissions test.
Stalling and misfiring Another sign of an EGR valve problem in your Audi A4 2.0 TDI is engine stalling. To run smoothly, an internal combustion engine needs three basic things- a properly balanced air-fuel mixture, optimal compression, and timely generation of electrical sparks. A faulty EGR valve can imbalance the air-to-fuel ratio within the combustion chamber, causing the engine to misfire and stall frequently. In addition to stalling, you may notice rough engine idle when you have EGR valve problems.
Bottom line The EGR valve is something that works in close coordination with the engine management computer and other important emission control systems to minimize NOx emissions. Failure of such an important piece of equipment can give rise to all sorts of engine-related troubles in your Audi A4. Therefore, if you are noticing any of the aforementioned signs of possible EGR valve problems, act fast and get professional help right away.