04 SLE P0420 code day after passes inspection

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Jdub34
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04 SLE P0420 code day after passes inspection

Post by Jdub34 »

Hey everyone. Like the title says I got that code immediately after passing emissions and inspection. What are the odds of that? Exhaust has been louder than usual lately though but no obvious performance loss. Is it possible the shop bumped something loose that I could check or is it just coincidental timing and my cat is bad.
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luke_dubs
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Re: 04 SLE P0420 code day after passes inspection

Post by luke_dubs »

EVAP system could actually have a problem, or the oxygen sensors on either side of the cat are bad. I highly doubt that the cat is bad.
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nos4blood70
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Re: 04 SLE P0420 code day after passes inspection

Post by nos4blood70 »

At least it happened right after the inspection. Haha
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harofreak00
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Re: 04 SLE P0420 code day after passes inspection

Post by harofreak00 »

luke_dubs wrote:EVAP system could actually have a problem, or the oxygen sensors on either side of the cat are bad. I highly doubt that the cat is bad.
#-o Ummm, no. The P0420 is almost always a bad cat.
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Jdub34
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Re: 04 SLE P0420 code day after passes inspection

Post by Jdub34 »

Thanks guys. The exhaust is really rattling in the area of the cat so I'm thinking the crap came loose inside. Just crazy how it threw the code day after inspection.
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96 SSEi
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Re: 04 SLE P0420 code day after passes inspection

Post by 96 SSEi »

the pcm gets cat info directly from the O2 sensor near the cat - get that checked out first.
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MKMike
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Re: 04 SLE P0420 code day after passes inspection

Post by MKMike »

nos4blood70 wrote:At least it happened right after the inspection. Haha
:beerchug: Gives you a bit more time to address the issue.
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