Hydrocarbons too high during smog test!
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Joined: Aug 2003
Posts: 75
Likes: 0
From: Chandler AZ
High HC in smog test
Sorry for the late reply - just saw your post. I run a '99 with a 395RWHP Doug Rippie engine, actually on 3rd engine now, was still running original cats at 104,000 miles with a whole lot of track days, two One Lap of America tours, etc. Anyway, I failed HC. First test numbers: HC 1.83, CO 6.84, NOX 0.83. Put on a new set of cats and now HC 0.50, CO 0.01, NOX 0.24. Made no other changes, and the old cats did not show any particular problems. I felt that was a good place to start, as the exhaust smelled strong at idle. This was an Arizona test, I don't know what the CA standards are. Good Luck. 
Thread Starter
Team Owner
Joined: Mar 1999
Posts: 28,753
Likes: 9
From: San Jose/Bear Valley CA
CA Events Coordinator
Originally Posted by Ls1Rat
just interested if i want to do a blower install on my car. what's the big deal ?
VR
Drifting
Joined: Jun 2004
Posts: 1,627
Likes: 143
From: Goodyear Az
What I've done in the past on marginal cars is:
Change the oil
Make sure the motor and exhaust are HOT when you take it in
Keep the AC off to keep from turning on radiator fans
If still no dice, put in new cats
Change the oil
Make sure the motor and exhaust are HOT when you take it in
Keep the AC off to keep from turning on radiator fans
If still no dice, put in new cats
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Thread Starter
Team Owner
Joined: Mar 1999
Posts: 28,753
Likes: 9
From: San Jose/Bear Valley CA
CA Events Coordinator
1. look harder and you will find a few
2. start a new thread asking for smog legal S/C applications for your area.
3. try to help me out with the topic on my thread.
VR
2. start a new thread asking for smog legal S/C applications for your area.
3. try to help me out with the topic on my thread.
VR
Last edited by vetterdstr; Aug 7, 2004 at 12:01 AM.
Burning Brakes
Joined: Nov 2003
Posts: 1,217
Likes: 0
From: Introducing teh Offical Car of your dreams
Originally Posted by vetterdstr
1. look harder and you will find a few
2. start a new thread asking for smog legal S/C applications for your area.
3. try to help me out with the topic on my thread.
VR
2. start a new thread asking for smog legal S/C applications for your area.
3. try to help me out with the topic on my thread.
VR
I love # 2 
Wish I could help but rookie too....I am working my way towards a blower in about 5-6 months. Very interested in this issue. Please be sure to post the fix/problem when you find it
...I know you will I wish you the best of luck 
FWIW...I just barely failed HC on my daily driver...both idle and speed on a roller at a test only. Nox and Co were well within the range. Had a different mech check out everything possible. All was good and he suggested cats, 114k miles on the car. Took it to the dealer and had it all checked again. Everything was perfect. The engine and tranny were rebuilt at about 90k miles. I bit the bullet and changed the cats. Back to same test only smog shop I went....my HC at idle and speed was incredibly low...way way under the max #'s. Passed with flying colors. I doubt you have anywhere near 100k miles on the Vette though. I have heard thats when must cats go bad.
I like the ideas suugested by others to really heat up the cats before the test
Which cats do you have now ? Would a FI car use up cats faster ???
Last edited by C54EVER; Aug 7, 2004 at 12:17 AM.
Thread Starter
Team Owner
Joined: Mar 1999
Posts: 28,753
Likes: 9
From: San Jose/Bear Valley CA
CA Events Coordinator
the cats were installed 3,000 miles ago and they were operational during the test. Smog guy says they were working, otherwise the test would have come out worse than what it did. I have High flow cats, I forget what brand. I would venture to say that if the tune was right, the cats should last as long as an NA engine.
VR
VR
Last edited by vetterdstr; Aug 7, 2004 at 01:27 AM.
Drifting
Joined: Mar 2004
Posts: 1,437
Likes: 0
From: UNDER THE HOOD
Originally Posted by vetterdstr
1. look harder and you will find a few
2. start a new thread asking for smog legal S/C applications for your area.
3. try to help me out with the topic on my thread.
VR
2. start a new thread asking for smog legal S/C applications for your area.
3. try to help me out with the topic on my thread.
VR
2. I'm in your area
3. can you add methanol ?
Drifting
Joined: Jul 2000
Posts: 1,289
Likes: 1
From: the West is the best
Originally Posted by Ls1Rat
1.
2. I'm in your area
3. can you add methanol ?
2. I'm in your area
3. can you add methanol ?
Your first effort should be to arm yourself with what is legal. Go to the California Air Resources Board website and do some basic preparation.
Then, go to Magnuson, ATI's and Vortech's websites for further information.
I am sure others would provide more detailed and pertinent information addressing your issues if you would take the effort to start your own thread.
