Does your car have problems starting sometimes or it behaves strangely when accelerating? Among other possible causes, this can be a symptom of a clogged or faulty EGR valve. This is a quite simple and self-sustained system that doesn’t require any regular maintenance. Still, things like leaks or carbon build ups can render it inoperable and lead to various running issues. In this article, we will go explain how the EGR system works and learn how to tell if it is faulty.

What does the EGR system do?

Modern cars have several systems whose task is to lower the emissions by reducing NOx and CO content in the exhaust. One of them is the EGR, which stands for Exhaust Gas Recirculation. As the name may imply, it takes a certain amount of exhaust gases and recycles it back into the engine intake manifold. This lowers the oxygen content in the combustion mixture and causes lower combustion temperatures. This system is only active in certain conditions, and one of them is that the engine has reached an operating temperature. The core of this system is an EGR valve, which regulates the flow of exhaust gases towards the intake manifold. Newer engines also have an EGR cooler, which uses engine coolant to reduce exhaust gas temperature.

There are several possible failure points that could disable this system, and a stuck EGR valve is the most common one. This happens because of soot and carbon inside exhaust gasses that deposit inside the valve and stop it from movement. Depending on the position, this will cause either black exhaust smoke and hesitation under acceleration or starting issues. A faulty or jammed EGR valve will trigger the check engine light and there will be a corresponding error code. Another possible weak spot is the cooler, which may develop a leak that allows coolant into the EGR system itself.

Can I repair the EGR systems myself?

Cleaning the EGR valve is a quite simple job, as there are various special sprays and liquids for that job. However, this usually requires it to be removed from the engine, which comes with several potential obstacles. One of them is the access to the EGR valve and other components, which can be limited on modern engines. And just like with any exhaust related work, corroded bolts and other hardware can be hard to unbolt and may even snap.

How important is this service?

The EGR system is a quite simple and self-sustained system that doesn’t require any regular maintenance. Still, carbon build-ups inside the EGR valve or a leaking coolers can cause problems with its operation. Not only may this cause different engine running issues, but it can also lead to permanent damage. Although cleaning or replacing EGR components isn’t a complicated job, it comes with several potential obstacles. If you don’t have the right tools or don’t feel up to the job, consider hiring a professional. At FixMyCar, we have certified and seasoned technicians that can come to your home and solve all EGR system related issues. This will ensure that all important components are checked and your car is ready to hit the road.