Supermaxx headers didn't pass emissions
Thread Starter
Instructor
Joined: Dec 2003
Posts: 229
Likes: 0
From: Aurora Colorado
Supermaxx headers didn't pass emissions
I was wondering if anyone else has had trouble passing emissions with Supermaxx LT's & cats. My tuner tells me it happens all the time because
the cats won't lite up until 800 degrees. He gave me an " emissions tune "
today and it still won't pass.
Any input on the subject would be appreciated.
jg
the cats won't lite up until 800 degrees. He gave me an " emissions tune "
today and it still won't pass.
Any input on the subject would be appreciated.
jg
Burnout
Joined: Jan 2004
Posts: 1,437
Likes: 12
From: South Surrey (White Rock) British Columbia
Emissions
Originally Posted by James G
I was wondering if anyone else has had trouble passing emissions with Supermaxx LT's & cats. My tuner tells me it happens all the time because
the cats won't lite up until 800 degrees. He gave me an " emissions tune "
today and it still won't pass.
Any input on the subject would be appreciated.
jg
the cats won't lite up until 800 degrees. He gave me an " emissions tune "
today and it still won't pass.
Any input on the subject would be appreciated.
jg
I wont know for 2 years if I pass.(Next test date)
mrgil
Drifting
Joined: Apr 2005
Posts: 1,509
Likes: 1
From: Lafayette CA
Make sure the cats are hot, either by having the smog guy run it for 20 or 30 minutes before testing, or go out and run it hard and test immediately. At least that's what my smog guy says. Good luck! 
Race Director
Joined: Jun 2004
Posts: 19,459
Likes: 48
From: Schaumburg IL
CI 7-8-9-11 Veteran
St. Jude Donor '06-'10, '13
Did they do the "sniffer" test where they put the device in your tail-pipe? or did they just plug into your computer and run it that way?
Are you throwing any codes?
O2 sims are not going to help pass a sniffer test, only way I see is a really good tune, or putting the stock cats back on for the test(if its a sniffer test), and then swapping them back afterward.
Also as others have said, make sure you drive the car and get it nice and hot or yes , you will fail, and i don;t mean just letting it idle for a while at the emissions place... I normally drive mine good and hard for about 20min on the way to the emissions place.
Are you throwing any codes?
O2 sims are not going to help pass a sniffer test, only way I see is a really good tune, or putting the stock cats back on for the test(if its a sniffer test), and then swapping them back afterward.
Also as others have said, make sure you drive the car and get it nice and hot or yes , you will fail, and i don;t mean just letting it idle for a while at the emissions place... I normally drive mine good and hard for about 20min on the way to the emissions place.
Last edited by FrankTank; Jun 20, 2005 at 09:20 AM.
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Verdad Gallardo
Le Mans Master
Joined: Aug 2004
Posts: 6,408
Likes: 0
Originally Posted by James G
How did 02 sims help pass an emissions test ?
jg
jg
<--- No cats and still passed NY emmisions.
Supporting Tuner
Joined: Sep 2004
Posts: 51,896
Likes: 39
From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
CI 6-7-8-9-10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Originally Posted by SilverBulletZ06
Oops, I forgot that NY is using different emmisions then most places. If it's a real sniffer test it won't do crap. If they plug it into the computer for an OBD-II diagnnostic then it will prevent the codes from showing and therefore pass you.
<--- No cats and still passed NY emmisions.
<--- No cats and still passed NY emmisions.
Thread Starter
Instructor
Joined: Dec 2003
Posts: 229
Likes: 0
From: Aurora Colorado
No codes
Yes they do the sniffer test here( colorado ). After some discusssion with Dynatech I'm going to have the headers coated, theyr'e comming off tonight.
They ( dynatech ) already knew the cats wouldn't pass a sniffer.
Buyers of long tubes beware, if you are now or in the future be subject to a sniffer test have em coated BEFORE you put them on the car...... I wish I'd known that little piece of info. I don't think the problem is limited to the Supermaxx, I've talked to a couple of LG users that had the same problem.
They ( dynatech ) already knew the cats wouldn't pass a sniffer.
Buyers of long tubes beware, if you are now or in the future be subject to a sniffer test have em coated BEFORE you put them on the car...... I wish I'd known that little piece of info. I don't think the problem is limited to the Supermaxx, I've talked to a couple of LG users that had the same problem.
Originally Posted by FrankTank
Did they do the "sniffer" test where they put the device in your tail-pipe? or did they just plug into your computer and run it that way?
Are you throwing any codes?
O2 sims are not going to help pass a sniffer test, only way I see is a really good tune, or putting the stock cats back on for the test(if its a sniffer test), and then swapping them back afterward.
Also as others have said, make sure you drive the car and get it nice and hot or yes , you will fail, and i don;t mean just letting it idle for a while at the emissions place... I normally drive mine good and hard for about 20min on the way to the emissions place.
Are you throwing any codes?
O2 sims are not going to help pass a sniffer test, only way I see is a really good tune, or putting the stock cats back on for the test(if its a sniffer test), and then swapping them back afterward.
Also as others have said, make sure you drive the car and get it nice and hot or yes , you will fail, and i don;t mean just letting it idle for a while at the emissions place... I normally drive mine good and hard for about 20min on the way to the emissions place.
they are very accurate! 