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P0420 Code help!

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Old Jul 25, 2009 | 01:40 PM
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Default P0420 Code help!

Hello People,

I just got back from Autozone where I checked the codes (my engine light's on). I have a P0420 code relating to the exhaust/emission control. Any suggestions?

I have a Maggie, B&B Catback, and 74,000 miles and didn't have an issue up until recently. I've had the car since it had 52,000 miles and the previous owner mentioned he never had problems.

Thanks a lot!

Adrian
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Old Jul 25, 2009 | 01:47 PM
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I don't know that code personally, but it sounds like an O2 sensor issue.
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Old Jul 25, 2009 | 01:50 PM
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http://www.p0420.com/
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Old Jul 25, 2009 | 02:17 PM
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Simple solution. Get some long tube headers, remove the cats, get retuned and have your tuner get rid of the rear o2s.
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Old Jul 25, 2009 | 03:08 PM
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I get that one when my K&N intake tube comes off or starts leaking.
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Old Jul 25, 2009 | 09:12 PM
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emissions warranty is 80,000 miles depending on how cool you are with your dealer they may change them with no cost to you just had both of mine go out within two weeks of each other sometimes stealerships are good for something
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Old Jul 26, 2009 | 10:03 AM
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Hey Guys!

Thanks for all the suggestions! I am going to take a look at my intake to make sure that's all good.

I have so far installed 3/4 o2 sensors. I believe both rear sensors are new and I got no change. The one left to install is the front passenger sensor. It's a bitch to get to.

I didn't know we had 80K mile guarantee on emissions. Do you guys have any suggestions on Caddy dealerships in the Houston area that doesn't frown upon maggies?

Thanks again!

Adrian
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Old Jul 26, 2009 | 06:19 PM
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Sounds like your car just want to pull over a smoke a phat one bud! Is your radio stuck on 4:20 pm
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Old Jul 26, 2009 | 07:21 PM
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i believe its 8yrs or 80k, so get it in before you hit 80!

its a federal law, not a factory warranty. they have to replace your cats if they are not operating correctly. dont let them give you any crap about your mods voiding a warranty!

i dont know for sure if your O2 sensors would cause that code if they werent working right, but i really really doubt it. its your cat. and it wouldnt be the front O2s. the rears are the ones that make sure the cats are working properly....
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Old Jul 27, 2009 | 09:22 AM
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Originally Posted by SS#1230
i believe its 8yrs or 80k, so get it in before you hit 80!

its a federal law, not a factory warranty. they have to replace your cats if they are not operating correctly. dont let them give you any crap about your mods voiding a warranty!

i dont know for sure if your O2 sensors would cause that code if they werent working right, but i really really doubt it. its your cat. and it wouldnt be the front O2s. the rears are the ones that make sure the cats are working properly....
Thanks for the information, my CEL is on too and the code is 340/341. I have less than 80k, so they should honor the warranty.
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