Q: Check Engine Light coming on after repair to fix it

asked by on February 15, 2016

We had our car looked at, due to the Check Engine Light coming on, which was due to error code P0400. The mechanic inspected the car and said that it needed a new EGR valve. We set up an appointment to have that done, and upon arriving and looking at the car further, the same mechanic said that the EGR valve was fine, but the car needed a new EGR solenoid. We set up a third appointment to have this done. After replacing the part and resetting the codes, the mechanic said that the issue should be fixed. A few days later, we took the car for a drive and the Check Engine light came on again.

Some of these vacuum-operated EGR systems that your vehicle has can be a little tricky. There are a few different solenoids, and they can be hard to isolate and test to find the bad component. In addition to the solenoids, the EGR passages in the intake manifold and exhaust manifold can be clogged with carbon deposits as well. This would also cause your EGR system to set a code. I would ask for help from a mechanic at YourMechanic to look over your vehicle, diagnose the current cause of your Check Engine Light illumination, and make any necessary repairs to your EGR system.

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