EGR systems help reduce emissions, improving air quality and protecting the environment. This is accomplished by diverting a controlled amount of exhaust gases back into the intake, reducing the combustion temperature, and providing a “second burn” of the exhaust, both of which help the engine run cleaner. For more information about how EGR works, check out our previous article which takes a deep dive into the system.
This article is going to focus on some of the common issues that can plague EGR systems, the symptoms you may notice, and the repairs associated with getting it fixed.
The most common problem with EGR systems is the failure of the valve that controls the flow of exhaust gases. Depending on the vehicle, the valve is controlled with vacuum from the engine or an electrical motor.
The exhaust gas is dirty. The EGR valve can become caked with soot and carbon buildup over thousands of miles of driving, causing problems and eventual failure. This is particularly common on diesel engines, and on EGR systems that are integrated into the cylinder head.
Vacuum-actuated EGR valves are also prone to failure. If the vacuum supply to the valve becomes blocked or starts to leak, it won’t work properly. Electrical issues can cause the motor in an electrically actuated valve to stop working, too.
EGR problems can present with a range of symptoms. Nearly all of them impact drivability, so they aren’t hard to notice.
If the EGR valve is stuck open or closed, it will drastically impact the way your vehicle runs. For example, if the valve is stuck open at idle, you might notice rough running or stalling, as the engine is not getting sufficient fresh air. If the valve is not opening or closing properly, the engine will run very erratically. You might also notice your vehicle doesn’t have as much pep as it used to.
If the EGR valve fails, the check engine light can illuminate. Most of the time, you will notice other symptoms as the valve begins to act up before the light comes on.
When the EGR valve is stuck open, you might notice a drop in fuel economy. With the valve open, the intake air temperature will be lower, reducing efficiency.
An issue with the EGR will cause your vehicle to emit more and fail an emissions test.
Many of the symptoms associated with EGR problems can also indicate something else. For example, rough running and reduced gas milage could be the result of a faulty ignition coil or spark plug, and a check engine light can indicate a wide range of issues. Even if you suspect the EGR system is the cause of your problems, the best way to know for sure is to have an experienced technician take a look at your car or truck.
The teams of technicians at all of our locations have the skills and experience to diagnose and repair issues with your EGR system. From vacuum leaks to carbon buildup, we will get your car or truck running as it should. Lake City Auto Care has shops in CDA, Hayden, and Rathdrum Idaho. Give us a call or schedule an appointment online today!