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Dan
Dan, Technician
Category: Chevy
Satisfied Customers: 24469
Experience:  Independent Shop Experience, 2 Year Automotive Diploma, & Access to Information Database
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03 chevy impala 3400 eng code p0401 egr valve replaced it twice

Customer Question

03 chevy impala 3400 eng code p0401 egr valve replaced it twice light still comes on
Submitted: 6 years ago.
Category: Chevy
Expert:  Dan replied 6 years ago.
This means you have carbon deposits on the EGR ports. Remove the Exhaust Gas Recirculation (EGR) valve and throttle body to clean out ports with cleaner, rag, and hanger. Let me know if you have questions, thanks.
Customer: replied 6 years ago.
i clean all the ports and the tube was not dirty
Expert:  Dan replied 6 years ago.
Replace the PCV valve and if that doesnt help the problem may be low engine vacuum due to a leak. Let me know if you have questions, thanks.
Customer: replied 6 years ago.
the engine was tuneup and the pvc was replaced it had a vaccum leak a hose was bad i had replaced it.
Expert:  Dan replied 6 years ago.
The only other part that could cause the problem is the map sensor. If PCV is new and correct, passages are clean, egr is new, map sensor is working like it should then check the wiriming going to the egr to make sure its getting signal when commanded on.......and if so replace the powertrain control module.
Expert:  Dan replied 6 years ago.
Another expert also let me know he has seen a restricted converter cause this code so you could do an exhaust pressure test to see if thats the problem. Let me know if you have questions, thanks.