Hey guys, I have a 2002 S2000, been having a trio of codes, two were o2 sensor related (don't remember which, they were the result of a failed rear o2 sensor), and the P0420. I replaced the o2 sensor, and both of the first codes went away, but the 420 stayed. I just replaced the cat with a magnaflow direct fit (product 93462) and reset the codes, after 30 miles the code came back on. My only thought is a leak? I did use new gaskets while replacing the cat. Any one have this happen? Any suggestions or ideas would be greatly appreciated. I'd like to avoid the defouler trick if possible.

Thanks,
Graeme

 

How far have you driven it? See post #14 and report back sir.

https://www.s2ki.com/s2000/topic/870268-p0420-cel/

 

Sorry for the disappearing act. Tried everything I could to try fixing it but nothing helped. The anti-fouler trick seemed to work well enough to get through emissions, though. I believe I may have killed my ECU recently (through hasty wiring work). I will be ordering a used one soon and replacing the rear O2 sensor along with it in hopes that can fix my new issue along with my old one.