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DTC 16805 Warm up catalyst efficiency below threshold (bank 1).. I STFA and

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Old 01-06-2004, 06:34 PM
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Default DTC 16805 Warm up catalyst efficiency below threshold (bank 1).. I STFA and

only found reference to this code with aftermarket downpipes. I till have stock DP's. First really cold night, down to 20 or so. No, I didn't let it idle to warm up, started driving right away like I always do. CEL came on about 15 minutes after I started driving. Car runs fine. Rear o2 sensor? I haven't replaced thsoe yet, only the fronts.
Old 01-06-2004, 06:39 PM
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I asked about that several times but got no clear answers. I'm thinking warm up cats are going bad.
Old 01-06-2004, 06:40 PM
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Just clear and see if it comes back. Probably just the cold temps triggered it.
Old 01-06-2004, 06:41 PM
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How long have you had the CEL?
Old 01-06-2004, 06:42 PM
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For a few months. No performance loss but it's freaking annoying.
Old 01-06-2004, 06:43 PM
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Default I did clear. I'll see if it comes back in the AM.

But it's not THAT cold out; I was in 38 below last year withouit a CEL. Guess I'll see what happens in the AM.
Old 01-06-2004, 06:44 PM
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Got that right. Did they have to make the CEL so bright :-p
Old 01-06-2004, 06:45 PM
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You have to drive about 40 miles to have it come back if it throws the code.
Old 01-06-2004, 06:46 PM
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Default Guess my real question is what sensor triggers this? The rear O2? Or is there

another sensor on the cat?
Old 01-06-2004, 06:47 PM
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That's about a round trip to work for me.


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