Q. My 1997 Honda Accord 4 cyl VTEC keeps misfiring. The Check Engine Light first came on and gave me the code P0401. I replaced the EGR valve and a few weeks later the check engine light came back on and gave the same P0401 code
I figured that I just didn't clean out the carbon enough when I replaced the EGR valve so I figured it didn't need to be fixed right away. However, after a few weeks the engine started running rough and another code appeared, this time P0302. The check engine light also started flashing at me while driving.
The mechanic replaced all the spark plugs and wires replaced and cleaned all the valves but it did not fix the problem. The mechanic told me that the problem was with the new EGR valve and that it was defective, causing the misfire.
I replaced the EGR valve but the check engine light keeps flashing while I am driving and the engine continues to run pretty rough and the car keeps giving me the same two codes. Do you have any idea what the problem is or any advice about what to do?
Thank you,
Rich Friess
A. Diagnostic Trouble Code (DTC) P0401: Insufficient flow in the Exhaust Gas Recirculation (EGR) system. There are only two causes for this code, a blocked or bad Exhaust Gas Recirculation (EGR) valve or blocked EGR port in the intake manifold.
Diagnostic Trouble Code (DTC) P0302: Cylinder 2 misfire detected. This code could be the result of the EGR problem so that needs to be addressed first since this one may be corrected at the same time.
