Q: Car reluctant to accelerate as if not getting power

asked by on October 09, 2016

Recently I started having an issue with my car when I try to accelerate it seems reluctant to do that. The check engine light came on and the code read Po404 and also there was something about misfires. I got the EGR valve replaced but it didn't solve the problem. One thing I have noticed is that the problem goes away after driving the car for about 15 minutes.

Thank you in advance for any advice.

My car has 143000 miles.
My car has an automatic transmission.

Engine hesitates during acceleration Inspection $94.99 - $114.99 Get a Quote

Hi, thanks for writing in. Let me start by explaining one of the strong possibilities concerning the misfiring. When the EGR valve malfunctions, the engine cylinders can combust prematurely. The computer will then detect the issue and label it as a misfire. Another issue you may want to check would be the passages around the EGR valve. There can be a deposit of carbon in the valve that can cause the valve to malfunction. If these were not cleaned thoroughly when the EGR valve was replaced, then the problem would still exist. Considering the fact you just got the repair done, you may want to trace over their work and verify the repair is still holding. A wiring issue would also cause this code to set, and cause issues with the valve in the first place. Here at YourMechanic, we can have a technician come to your home or office to inspect and diagnose this issue for you, and make or suggest the necessary repairs.

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