Just found out that I had this code. CEL came on tonight - no drivability issues. What should I look for as the resolution if the code returns - as I cleared it. 2005 Acura TL 132k and I do need an oil change.

 

Seems to be EGR related. Easy fix if its related to carbon accumulation. Buy new EGR gasket, remove egr valve, clean with carb cleaner. You should be good to go

 

Sorry..... thats the incorrect code..... p0420

 

It's your catalytic converter located behind the engine wedged between the firewall. Leave it be. If the CEL takes a while to come on, that's your way to pass emissions. The car has 3 cats anyway...

 

I'm not in a location where emissions is tested. Is it definitively the cat and not the O2 sensor? I was told it could be both possibly but not sure if this is a known code thus leading to one over the other as the probable cause.

 

had a P0420 before and it says o2 sensor but cmon issue on our J series engines is it's the Cat. in CA we needed emissions so i had to drop 600 big ones for a new OEM cat.. no more issue.

 

Polish pat is correct. Clean the EGR and also clean the Intake manifold.


I had the same code a few years back and was about to go buy the EGR. However, a buddy of mine was like just clean it. We did and haven't had that code pop up again.

 

Still having this issue with P0420 - Do we simply need to replace the Cat or both cat and sensor to resolve this?

Also, will this lead to an open exhaust smell in the car if it progresses to becoming worse?