[OneOfAKind.6.0]

So to start off, I replaced my catalytic converters, between the radiator and firewall, in October of 2021 and since then I have been having P0430 and P0420 codes coming back repeatedly. I have no exhaust leaks that I’m aware of. I just relaxed the third converter after the y-pipe this past Friday, January 20th 2023. In between replacing the converters in the past year and a half, I have replaced the gasket between the y-pipe and 3rd converter maybe 2 or 3 times. I have replaced all 4 HO2 sensors twice, I just replaced them the second time within the past month and I’m still getting these codes. I can’t figure out what the issue is for the life of me, which sucks because my tags expire in the middle of February and I’m running out of time to figure this out and get it fixed. I don’t have the funds to take it to a shop and spend hundreds of dollars to get it figured out so that makes it even more difficult.

 

[SaturnFan]

Did you break in your gaskets? I replaced my cats too as i was having problems and even though i broke mine in one of the gaskets split like 2 weeks later so that could also be an issue. Other than that maybe your engine is burning oil? Before i replaced my engine i was getting the same codes.

 

[OneOfAKind.6.0]

How do I break in gaskets?

 

[SaturnFan]

Sorry i meant did your break cats in? its been a while since i worked on my exhaust and somehow thought it was gaskets lol

 

[OneOfAKind.6.0]

I still don’t know how to break in cats lol, that could likely be my issue

 

[SaturnFan]

that might be, or your cats were too cheap and cant meet emissions, idk what kind of kit you bought or if they were OEM. Catalytic Converter Break-In I followed these directions to break them in when i installed mine and its working pretty well, I'd try any other ideas first though before you throw another set of cats at it.

 

[joe45c]

Do you think you might have a vacuum leak somewhere. Saw that in a utube video where a guy said the code will keep coming back if you have a vacuum leak.