Alright, so I deleted the secondary cats and resonator about a year ago and I'm selling my vehicle as a trade through a buy bid at my dealership and the stupid CEL has thrown an O2 code on the right side since the delete.... So I tried getting defoulers to essentially trick the ECU but that's not working too well. My question is, where the hell can I get the most inexpensive cats to put back on and just be done with the damn thing?
My biggest mistake was to not keep them....
My biggest mistake was to not keep them....

Junior Member
If you cut the secondary cats, you should not be throwing a code. Did you replace the O2 in question?
Quote:
That's what I've been told before but it started within about 2 days of the delete and when I reset it it stays off for about 2-3 days then comes back on... I just figured it was the delete. Could they literally just be bad O2 sensors?Originally Posted by hebdog
If you cut the secondary cats, you should not be throwing a code. Did you replace the O2 in question?
I did not actually try replacing the sensor(s).... Guess now is a crappy time to start trying to figure all this out.
Senior Member
Just saw your car on craigslist... Looks clean! What dealership are you selling it to/work at? I would try replacing the actual o2 sensor before trying to re-install the cats.
Quote:
Okay, guess we'll do that. Damn...Originally Posted by Enigma94
Just saw your car on craigslist... Looks clean! I would try replacing the actual o2 sensor before trying to re-install the cats.
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shardul
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It is probably a bad 02 sensor
I know there's a before and after sensor, is there a way to tell if both or just one?
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shardul
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- Join DateMay 2008
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Well the CEL code should tell you which one is going bad
Quote:
Yeah I had the codes written down, we'll scan it again on Monday and if it's a part I can get locally we'll just get whichever is throwing the code and replace and hopefully it'll work.Originally Posted by shardul
Well the CEL code should tell you which one is going bad
Junior Member
The code will tell you which sensor it is, being up or down stream and which bank, being driver or passenger. It is merely coincidence that you had a O2 fail shortly after the cat delete. If you have a code the worst thing you can do is ignore it by deleting it. The problem is still present hence why the PCM notified you of the issue. Let me know what codes are in the PCM and I can help you with which sensor(s) it is. 
Thanks a lot for your help gentlemen! Tomorrow morning I'll scan the computer and post the codes. I appreciate the help.