Q: Replaced EGR valve and cleaned the intake but the P0401 code is still coming up after reset

asked by on October 26, 2016

Replaced egr valve and cleaned the intake but the p0401 code is still coming up after reset

My car has 161000 miles.
My car has an automatic transmission.

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Hi. There could be carbon build up in the ports under the EGR valve causing it to still throw the code for the EGR valve. There is also the possibility that the part you purchased is defective and that’s why the code is coming back on. There also could be damaged wiring to the EGR valve or the connector for EGR valve is broken or had corrosion in it. Causing a bad connection making the light come. In some rare cases the PCM (Power Control Module) is faulty causing the code for EGR valve to on even though the part is new. To avoid any unnecessary repairs, I suggest you have a certified technician from YourMechanic come to your home for a diagnosis of your car’s trouble code.

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