aamirghanchi

Hi,

I have 2003 Civic Hybrid. I am getting check engine light and am pulling P420 code. It is probably the cat converter that has gone bad. When I checked under the car I see two cat converters! which one should I get replaced. Is it both?

Thanks.

johndeerebones

Where are the sensors? The P0420 is catalyst efficiency. The ECM doesn't see enough difference between the primary and secondary 02 sensors. Either one or both is sensed.

ezone

This should answer the question if you can muddle through the alphabet soup: http://www.tegger.com/hondafaq/p0420/A050100.pdf


Be aware that there have been software updates that address the P0420 codes, among many other issues. See your Honda dealer and have all the updates done first, THEN if it resets the cat code go ahead and replace it.

Some of these software updates were campaigns, and could possibly still be covered under a warranty extension. Your dealer would have to do a VIN inquiry in order to find out the status of your car.

aamirghanchi

Hey Thanks for the link! Although I'm sure all recalls have been taken care of on my HCH, still I will double check with the dealer if there was anything that got left out.

It really does have two cat cons! The front one is part of the exhaust manifold and they all need to be replaced together, what a ripoff!
Code 0420 indicates the front one gone bad. Otherwise it would have been easier to replace the downstream one which is simply nuts and bolts.
Don't know how much will they charge me if it really comes down to replacing the front one.

Thanks all!