Questions and Answers

Honda Accord DTC P0420 Q. Vincent, I have a 1998 Honda Accord EX V-6. I been having problems with my check engine light coming on and going off. The first few times I took it the Honda dealership and they diagnosed a EGR Valve problem. They clean it, the light went off and sent me on my merry way. After about four times, I was beginning to get upset.

The dealership performed some "service bulletin" that was covered under the 80,000 mile warranty that would supposedly fix the problem. The light went out but subsequently came back on. This time the code was P0420 "Catalyst system efficiency below threshold (bank 1)".

I replaced the catalytic converter with non-Honda catalytic converter. The light constantly goes out and comes back on. This is accompanied by rough driving. Upon pushing the "gas pedal" there is a slight hesitation and then a jerk (as if something was wrong with the transmission).

I have read several web sites about various other Honda owners having the same problem. I don't know what to do. Will a new Honda converter fix the problem? I asked at the Honda dealership and they are talking $1000.00 to install a new one. What about a remanufactured converter?

I am looking for an unbiased answer from someone with no underlying motives. Any help you have would be appreciated.

Thanks,
Darryl

A. DTC P0420 does indicate a bad catalytic converter. It would not be surprising to see an aftermarket universal catalytic convertor not working well enough or have the capacity to turn the light off.