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

asked by on

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.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Check Engine Light coming on after repair to fix it

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: The fan clutch will not disengage.

Hi there. The fluid that is inside the fan clutch has leaked out and is no longer keeping the clutch is a slipping mode until it gets hot. I recommend replacing the fan clutch assembly. If you need further assistance...

Q: AT light and Check engine light on stuck in third gear.

A logical place to start is with a Check Engine Light inspection to see what codes might be set. Usually with something of this nature, codes will be present, and there will be a flow chart that should be used...

Q: Q: Burning smell from car

Was the garage closed or open? Have you noticed this smell at any other time? There may not be a problem at all. Remember that catalyst converters get hot and cars run a lot hotter than they use to. Perhaps...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...