Hydrocarbons too high during smog test!
Thread Starter
Team Owner
Joined: Mar 1999
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From: San Jose/Bear Valley CA
CA Events Coordinator
Hydrocarbons too high during smog test!
Had my car tested today, hydrocarbons were too high. Has anyone encountered this? if so what did you find wrong with the car? how did you fix it?
TIA, VR
TIA, VR
Thread Starter
Team Owner
Joined: Mar 1999
Posts: 28,753
Likes: 9
From: San Jose/Bear Valley CA
CA Events Coordinator
I the interest of being fair I will answer your post.
Thanks for the humor.
I know the car is running rich. 
Now getting back to my questions, can you help me with any of them?
VR
Thanks for the humor.
I know the car is running rich. Now getting back to my questions, can you help me with any of them? VR
Last edited by vetterdstr; Aug 4, 2004 at 08:14 PM.
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
are there any faults stored?probably not.before the sniff test,did the car idle for a while?if so,the cats probably cooled down.you said you only failed hc,so i'm assuming you passed co,if you were running rich,you would of flagged co and maybe hc.i see you are supercharged and with your hp/tq #'s you are tuned also.high hydrocarbon's and good co usually means lean fuel mixture/weak ignition system[plugs,wires,etc.]/cool cats,etc.without seeing the car,it's tuff to say.if you have the access to a scan tool,look at the fuel trims if anything you may have to fatten her up a bit to bring the hc down[if there are no air/vacuum leaks,good fuel pressure,good ignition,etc.
NOTE:if the car idled for a while before the test,it is very possible the cats cooled off and being a forced car,the hc began to climb.try it again,but before they sniff you,run the car up around 3 grand for 5 minutes,this should make enough heat to fire up the cats.
NOTE:if the car idled for a while before the test,it is very possible the cats cooled off and being a forced car,the hc began to climb.try it again,but before they sniff you,run the car up around 3 grand for 5 minutes,this should make enough heat to fire up the cats.
Thread Starter
Team Owner
Joined: Mar 1999
Posts: 28,753
Likes: 9
From: San Jose/Bear Valley CA
CA Events Coordinator
No codes in the computer. CO #'s were very very low... Mechanics gut feeling is a vacuum leak somewhere. I will look over everything you talked about before going back to the shop to have him check out the things I dont know how to do.
Thanks man!!
VR
Thanks man!!
VR
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
if your co is that low,your long term fuel trims have to be high +[+18-+20],+25 turns the check engine light on.if you have a vacuum leak,it should be loud enough to hear.also look for air leaks after the maf,etc.,if everything check out[air/fuel pressure/ignition,etc.].have who ever tuned it,fatten her up a bit to bring your fuel trims down.
Thread Starter
Team Owner
Joined: Mar 1999
Posts: 28,753
Likes: 9
From: San Jose/Bear Valley CA
CA Events Coordinator
My blower is so loud that it would be hard to hear a vacuum leak... If everything else does check out I will have to travel 400 miles one way to have the computer tuned... as it is, I had them do a conservative (rich) tune so my engine would stay together.
Melting Slicks
Joined: Apr 2004
Posts: 2,301
Likes: 199
From: Valencia CA
IMHO, Generally speaking the cats help post process the exhaust to lower hydrocarbon emissions. If your NOX was low then it needs some timing advance to help heat up the combustion chamber and burn the excess fuel which could also heat up the exhaust gas temp and help light off the cats sooner. Which will also raise NOX. Then again I'm just a Rookie. Hope this helps!
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Melting Slicks
Joined: Jun 2002
Posts: 3,060
Likes: 3
From: Dublin CA
Had that problem, failed 'HCs at idle' due to lopey cam. Solved when it went to referee station and was run on rollers at 1500rpm and 3000rpm.
Each county is different, I was told by smog people that the ocean breeze moves smog between counties, and inland counties force seaside counties to tighten their smog. Inland counties get away with looser requirements. Do you have to get smogged in Santa Clara county?
Each county is different, I was told by smog people that the ocean breeze moves smog between counties, and inland counties force seaside counties to tighten their smog. Inland counties get away with looser requirements. Do you have to get smogged in Santa Clara county?
Melting Slicks
Joined: May 2003
Posts: 2,851
Likes: 1
From: San Bruno Ca
DO a scan test of your car and stop guessing. Do you know of anybody with a scan program on a laptop? I have a Ease scanner program and can scan your car if you can't find anyone to do this for you. Then you can do an LS-1 edit to get it running the way it should be.
Melting Slicks
Joined: May 2003
Posts: 2,851
Likes: 1
From: San Bruno Ca
Originally Posted by vetterdstr
My blower is so loud that it would be hard to hear a vacuum leak... If everything else does check out I will have to travel 400 miles one way to have the computer tuned... as it is, I had them do a conservative (rich) tune so my engine would stay together.
if you already don't own one. ALso get a scan program. I hear the HP tuner program comes with it's own scanner, but As of now, there are not too many people who supports that program yet.
Le Mans Master
Joined: Jul 2002
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From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
Originally Posted by Scubanme
You can have your PCM tuned right at home if you own an LS1-edit program. With all your mods, you should go out and obtain an LS-1 edit
if you already don't own one. ALso get a scan program. I hear the HP tuner program comes with it's own scanner, but As of now, there are not too many people who supports that program yet.
if you already don't own one. ALso get a scan program. I hear the HP tuner program comes with it's own scanner, but As of now, there are not too many people who supports that program yet.
The best move I ever made was buying HPtuner, in a situation like this you can run the scanner and record your LTFT and make any change you like.
Thread Starter
Team Owner
Joined: Mar 1999
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From: San Jose/Bear Valley CA
CA Events Coordinator
I had LS1 edit and after a fried computer 1.5 years ago, I really dont think it works on my car anymore. A local guy had all the stuff, scanning, tuner version of LS1 edit. He ran traces on my car 8 or 9 times, tuned my car 4 or 5 times.
Recently I had traces run on my car another 8 times and had the car tuned twice. So my understanding is that everything in those departments are supposed to be tip top shape.
VR
Recently I had traces run on my car another 8 times and had the car tuned twice. So my understanding is that everything in those departments are supposed to be tip top shape.
VR
Last edited by vetterdstr; Aug 5, 2004 at 09:35 AM.
Thread Starter
Team Owner
Joined: Mar 1999
Posts: 28,753
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From: San Jose/Bear Valley CA
CA Events Coordinator
Originally Posted by blu00rdstr
Had that problem, failed 'HCs at idle' due to lopey cam. Solved when it went to referee station and was run on rollers at 1500rpm and 3000rpm.
VR
Le Mans Master
Joined: Feb 1999
Posts: 6,269
Likes: 1
From: Richmond Ca
Originally Posted by vetterdstr
I had LS1 edit and after a fried computer 1.5 years ago, I really dont think it works on my car anymore. A local guy had all the stuff, scanning, tuner version of LS1 edit. He ran traces on my car 8 or 9 times, tuned my car 4 or 5 times.
Recently I had traces run on my car another 8 times and had the car tuned twice. So my understanding is that everything in those departments are supposed to be tip top shape.
VR
Recently I had traces run on my car another 8 times and had the car tuned twice. So my understanding is that everything in those departments are supposed to be tip top shape.
VR
Thread Starter
Team Owner
Joined: Mar 1999
Posts: 28,753
Likes: 9
From: San Jose/Bear Valley CA
CA Events Coordinator
FWIW, the fuel was run conservative on the top end to keep the motor from going lean, the timing is running at 23 deg (which is 8 deg more than 99% of FI engines) I could reprogram the computer just to pass smog, if I have a mechanical problem then I would rather get it found and fixed.
I will go back to the shop today with everyones input, hopefully he will find a mechanical problem, fix it and then it will pass ok.
Thanks, VR
I will go back to the shop today with everyones input, hopefully he will find a mechanical problem, fix it and then it will pass ok.
Thanks, VR
