Found my smog problem. (I hope)
Team Owner
Joined: Dec 2000
Posts: 24,906
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From: Swords Check/Saws Check/Clubs Check/Claws Check/Hatred Check/Anger Check/Murmaid Check/Murder Check
Cruise-In IV Veteran
Cruise-In VI Veteran
Re: Found my smog problem. (88'Cubka)
Yeah... that could be a problem :crazy: :thumbs:
Le Mans Master
Joined: Jul 1999
Posts: 9,206
Likes: 17
From: Sewell NJ
Re: Found my smog problem. (88'Cubka)
Not unusual, mine was the same way when I took off my intake. What kind of problem are you having. If your car isn't passing the sniffer test at idle I don't think the clogged intake would effect it. i thought that the the EGR doesn't function at idle but only when the car is underway. I might be wrong on this but a clogged EGR passage would probably make no more difference than blocking off the EGR altogether. :confused:
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Re: Found my smog problem. (vettfixr)
I always ran blocked off gaskets back when I had heads or manifolds with the cross over exhaust passage just to keep intake heat down. EGR is not the way to obtain power.
I'm busy with out of country guests this weekend, but I'm free next week to look at it
I'm busy with out of country guests this weekend, but I'm free next week to look at it
Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,321
Likes: 0
From: Reno NV
St. Jude Donor '08
Re: Found my smog problem. (gkull)
It's failing hydrocarbons at Idle really bad. one i have is 3000ppm when detuned, and 5000 at factory specs. Pass is less than 500. I think I have a nice miss or 6 at idle, lol.
Le Mans Master
Joined: Jul 1999
Posts: 9,206
Likes: 17
From: Sewell NJ
Re: Found my smog problem. (88'Cubka)
Fixing the EGR problem is not going to help your emissions. The EGR is non-functional at idle. As you crack the throttle vacuum is applied to the EGR and a small amount of exhaust gas is allowed to mix in with the intake charge. This continues until you are about half throttle. After that, when the intake vacuum drops the EGR becomes non functional again. It's a good idea to clean everything up but I would start looking at the carb or ignition to fix the emissions problem. Sorry for the bad news. :sad:
Team Owner
Joined: May 2001
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From: Exiled to Richmond, VA - Finally sold my house in Murfreesboro, TN ?? Corner of "Bumf*&k and 'You've got a purdy mouth'."
CI 6-7-8 Veteran
CI-VIII Burnout Champ
St. Jude Donor '06-'10, '13
Re: Found my smog problem. (vettfixr)
If your failing HC by that much it sounds like you are way too rich. I wonder if you are firing on all 8.
When was the last time you did your yoga practice ? It may be time to replace all the plugs. Look at them and see if your running rich.
I had a broken plug that was not firing that cause a similar problem.
When was the last time you did your yoga practice ? It may be time to replace all the plugs. Look at them and see if your running rich.
I had a broken plug that was not firing that cause a similar problem.
Melting Slicks
Joined: Jun 2001
Posts: 2,429
Likes: 14
From: CA
Re: Found my smog problem. (88'Cubka)
With a plugged EGR, your NOX would show high on the rear wheel dyno type smog machines they use in Cal.
High HC is a rich running condition or not getting full burn. When you take it in for the test, make sure the motor is hot (drive it on the freeway for 10 minutes). When you get there, don't shut it off to fill out the paperwork.
Make sure the choke is opening fully. Also, check the thermostatic air cleaner - it shoud be wide open too. A plug change may help too - Go 1 or 2 steps hotter for smog testing purposes.
Is the smog pump functioning OK?
Also, do you still have the catalitic converter?
High HC is a rich running condition or not getting full burn. When you take it in for the test, make sure the motor is hot (drive it on the freeway for 10 minutes). When you get there, don't shut it off to fill out the paperwork.
Make sure the choke is opening fully. Also, check the thermostatic air cleaner - it shoud be wide open too. A plug change may help too - Go 1 or 2 steps hotter for smog testing purposes.
Is the smog pump functioning OK?
Also, do you still have the catalitic converter?
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Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,321
Likes: 0
From: Reno NV
St. Jude Donor '08
Re: Found my smog problem. (71coupe)
With a plugged EGR, your NOX would show high on the rear wheel dyno type smog machines they use in Cal.
High HC is a rich running condition or not getting full burn. When you take it in for the test, make sure the motor is hot (drive it on the freeway for 10 minutes). When you get there, don't shut it off to fill out the paperwork.
Make sure the choke is opening fully. Also, check the thermostatic air cleaner - it shoud be wide open too. A plug change may help too - Go 1 or 2 steps hotter for smog testing purposes.
Is the smog pump functioning OK?
Also, do you still have the catalitic converter?
High HC is a rich running condition or not getting full burn. When you take it in for the test, make sure the motor is hot (drive it on the freeway for 10 minutes). When you get there, don't shut it off to fill out the paperwork.
Make sure the choke is opening fully. Also, check the thermostatic air cleaner - it shoud be wide open too. A plug change may help too - Go 1 or 2 steps hotter for smog testing purposes.
Is the smog pump functioning OK?
Also, do you still have the catalitic converter?
Thanks,
David :cheers: