stupid emissions.
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Le Mans Master
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From: Fort Worth Texas
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stupid emissions.
I failed the 'new' Texas dyno emissions test. Just barely. I passed the 25mph test, but failed the 15mph test. They said the usual cause of high Nox is a bad Cat or EGR. My cat is only 9 months old. I guess I can check EGR valve function. Anything else I can check?
I am thinking of just tuning it to run dangerously lean, run down there, pass emissions, then put my chip back in.
I haven't tuned my chip since February.... I guess I need to check it a little closer. :mad
I am thinking of just tuning it to run dangerously lean, run down there, pass emissions, then put my chip back in.
I haven't tuned my chip since February.... I guess I need to check it a little closer. :mad
Team Owner
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From: Athens AL
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Re: stupid emissions. (Marcho Polo)
I am thinking of just tuning it to run dangerously lean, run down there, pass emissions, then put my chip back in.
Team Owner
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From: SE NY
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Re: stupid emissions. (Marcho Polo)
Check that the O2 sensor is working. Jumper ALDL pins A&B, start the engine, after a copla minutes raise idle to about 2,000-2,500rpm. Observe that the SES flashes should settle to about 1Hz and be of equal On/Off duration both at low idle and at high idle. If not replace the O2 sensor.
If the EGR was not functioning the ECM would throw the dreaded code 32.
You can put some dry gas in the tank just before the next check to cut NOx, and have the car warmed up fully before turning it over to them.
If the EGR was not functioning the ECM would throw the dreaded code 32.
You can put some dry gas in the tank just before the next check to cut NOx, and have the car warmed up fully before turning it over to them.
Melting Slicks
Joined: Nov 2000
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From: X
Re: (scorp508)
$100 goes a long way with the emissions guys. ;)
http://www.cga.state.ct.us/2002/olrd...002-R-0178.htm
Melting Slicks
Joined: Apr 2002
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From: Clever, MO aka SOMO
Re: stupid emissions. (Marcho Polo)
Here in California, the egr is usually the main culprit. My '88 didn't pass at first either and they suggested replacing the egr. I went home, got an new egr valve, pulled the plenum, installed the new egr, went back to the testing station and passed with flying colors. They even stated that my car was one of "cleanest" emissions tested cars that they had ever seen. I felt pretty good after that comment.
Good luck,
Fix
Good luck,
Fix
Thread Starter
Le Mans Master
Joined: Mar 1999
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From: Fort Worth Texas
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Re: stupid emissions. (fixvet)
Here in California, the egr is usually the main culprit. My '88 didn't pass at first either and they suggested replacing the egr. I went home, got an new egr valve, pulled the plenum, installed the new egr, went back to the testing station and passed with flying colors. They even stated that my car was one of "cleanest" emissions tested cars that they had ever seen. I felt pretty good after that comment.
Good luck,
Fix
Good luck,
Fix
I think I need to replace my egr valve anyway. Can't find on in stock anywhere right now.
I may try to tune the chip to run as lean as I can, and then run some of that stuff in my gas.
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Re: stupid emissions. (Marcho Polo)
Damn man...suxs to hear about this...Hope a new EGR fixes ya up.They want that part throttle test via EGR band done these days eh?
Craig,what color or how are your plugs doing?Wheres your TPS set too?Im just asking since its hard to imagine if your car runs fine with the EGR now,a new one will fix it? It just opens and closes.
Check the carbon in the egr system as well.
Good Luck.
emissions testing= :boxing
Craig,what color or how are your plugs doing?Wheres your TPS set too?Im just asking since its hard to imagine if your car runs fine with the EGR now,a new one will fix it? It just opens and closes.
Check the carbon in the egr system as well.
Good Luck.
emissions testing= :boxing
Race Director
Joined: Aug 2002
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From: Kentucky
Re: stupid emissions. (FSTRNU)
They test here in the county that I live,and my cars are registered in a different county just for that reason. Anyway, I have heard of some people having good luck with a product called guaranteed to pass. If you just barely failed it might be worth trying.
Pro
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From: Eagle IDAHO
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Re: stupid emissions. (castivers)
Hmmmm, kinda makes me wonder how my car would fare on the test with no EGR at all. My Iron Eagle heads don't have an EGR passage, and I don't use the 86> pipe from the header to the manifold. Don't get no codes either. Did you eliminate EGR from my chip Craig? Obviously we don't have smog testing up hear in new hamster.
Le Mans Master
Joined: Dec 1999
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From: And on the fifth day, subpoenas were served to Obama senior staff
Re: stupid emissions. (Marcho Polo)
I may try to tune the chip to run as lean as I can, and then run some of that stuff in my gas.
My opinion is the EGR dutycycle in these chips does not play well with the IM240 test. Check it out with a scanner under similar conditions.
Some dry-gas HEAT may help reduce combustion temps and NOx, but be careful with your injectors.
Good Luck and lets us know how it works out for you.
Pete
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From: Alive and well in Burlington NC
Re: stupid emissions. (65Z01)
You can put some dry gas in the tank just before the next check to cut NOx, and have the car warmed up fully before turning it over to them.
Safety Car
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From: Pinellas Florida Misfit
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Re: stupid emissions. (Steel Blue 91)
You can also set the coolinmg fans to come on much later for testing.. hotter cars run cleaner. A lot of the GN guys would just pull the low speed fan relay.. engine would run hotter then normal and they'd pass with flying colors... even with no cat :)
Le Mans Master
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From: Memphis, Tn
Re: stupid emissions. (PeteL)
PeteL hit the nail on the head. NOx and CO run inversely. As NOx goes up, CO goes down, and vise versa. Lean makes NOx go up and CO go down.
In addition to his suggestions, I would also find out who sells low sulfur gasoline in your area. Around here, and in many parts of the country, Amoco Premium is low sulfur. Sulfur in gasoline will deactivate the cat converter. But it is reversable. Just run a tank or 2 or low sulfur gasoline. Also, just before the test, run the car real hard to heat up the cat converter. A hot converter works better than a cool one.
And as someone else mentioned, retarding the timing will help lower NOx. Good luck.
In addition to his suggestions, I would also find out who sells low sulfur gasoline in your area. Around here, and in many parts of the country, Amoco Premium is low sulfur. Sulfur in gasoline will deactivate the cat converter. But it is reversable. Just run a tank or 2 or low sulfur gasoline. Also, just before the test, run the car real hard to heat up the cat converter. A hot converter works better than a cool one.
And as someone else mentioned, retarding the timing will help lower NOx. Good luck.
