Removing Pre-Cats....will it throw error codes?
Thread Starter
Instructor
Joined: Nov 2002
Posts: 174
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From: West Columbia SC
Removing Pre-Cats....will it throw error codes?
If i gut my pre-cats....will i have to trick the O2 sensors?? I REALLY want to gut them, or just have them cut out altogether. Do I need to do anything else?
:cheers:
:cheers:
Team Owner
Joined: Apr 2001
Posts: 54,204
Likes: 180
From: S.W. Ohio. . . . . . NRA Life Member
Re: Removing Pre-Cats....will it throw error codes? (JWD01)
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Burning Brakes
Joined: Apr 2001
Posts: 802
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From: Lincoln NE
Re: Removing Pre-Cats....will it throw error codes? (vstella)
You gutted all 4 without throwing codes?
I would think gutting the precats would have to give you a few HP - that material has to restrict air flow quite a bit.
I would think gutting the precats would have to give you a few HP - that material has to restrict air flow quite a bit.
Drifting
Joined: Sep 2001
Posts: 1,393
Likes: 1
From: Fort Lauderdale Florida
Re: Removing Pre-Cats....will it throw error codes? (vstella)
I pulled all 4 of mine..installed a set of 02 sims...No codes :yesnod:
Le Mans Master
Joined: Nov 2000
Posts: 7,294
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From: Coral Springs Florida
Re: Removing Pre-Cats....will it throw error codes? (Ben01C5)
I pulled all 4 of mine..installed a set of 02 sims...No codes :yesnod:
Is the exhaust smell to strong, with no cats on? I don't know if I want all mine off or not. No emissions in Fla. ....Ben01C5
Is the exhaust smell to strong, with no cats on? I don't know if I want all mine off or not. No emissions in Fla. ....Ben01C5
Team Owner
Joined: Apr 2001
Posts: 54,204
Likes: 180
From: S.W. Ohio. . . . . . NRA Life Member
Re: Removing Pre-Cats....will it throw error codes? (99Mongoose400SS)
I would think gutting the precats would have to give you a few HP - that material has to restrict air flow quite a bit.
:yesnod:
Instructor
Joined: Dec 2001
Posts: 169
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From: VA
Re: Removing Pre-Cats....will it throw error codes? (PalmettoVetteMan)
My greatest concern about gutting the pre cats, is if it would cause the car to fail an emissions test. Here in good ol' MD, we have to get our cars tested every 2 years.
Anyone still passing the emissions tests with gutted pre cats?
Anyone still passing the emissions tests with gutted pre cats?
Melting Slicks
Joined: Oct 2001
Posts: 2,480
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From: Wa.
Re: Removing Pre-Cats....will it throw error codes? (Michaeljh2000)
The pre-cats are for cold start emissions. Gutting them should have no effect on the emissions once the vehicle is at operating temperature. :cheers:
Melting Slicks
Joined: Dec 2001
Posts: 2,040
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From: Collin County Texas
Re: Removing Pre-Cats....will it throw error codes? (JWD01)
Z06 does not have the pup cats.
Gary, when will you get your car tuned? And where? I thought if it was out at LGM, I would stop by. They are only 5 minutes east of me. I have a new toy, EFILive. That is all I need, something else to play around with!
Gary, when will you get your car tuned? And where? I thought if it was out at LGM, I would stop by. They are only 5 minutes east of me. I have a new toy, EFILive. That is all I need, something else to play around with!
Team Owner
Joined: Apr 2001
Posts: 54,204
Likes: 180
From: S.W. Ohio. . . . . . NRA Life Member
Re: Removing Pre-Cats....will it throw error codes? (RWhite)
Anyone still passing the emissions tests with gutted pre cats?
As mentioned above, the precats are only effective on a cold startup. If the Gore test doesn't require the car be left overnight so the test can be performed with a stone cold engine... they you will pass with no problems due to the pre-cat gutting. If you actually remove the precats and replace them with a straight pipe... then you might fail the visual inspection.
