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Thread: Failed CT emissions test

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Posts: 11-20 of 22
2013-12-30 12:48:07
Cory, take it up to Jimmi and he'll give you a hand. You really need to do back-to-back runs as you adjust things. It's not always as simple as it seems. I gave Jimmi a 91 SE-R and he had to run it 7 times before it passed. Luckily this will be your last time. 25yrs old in CT and you are exempt. make sure it passes in 2014 though. Otherwise you will have to test again. When was it due?

2013-12-30 13:36:54
The car last passed in 2011 so it is way overdue....
2013-12-30 16:30:03
Put a "restrictor plate" on the exit of the cat. It will make the cat hotter, and reduce NOx, as a result.

Cut a piece of sheet metal in the shape of the cat gasket. Drill 8 or so 1/4" holes in it, bolt the cat back to the exhaust with the plate in between.

Pull timing out of it, as mentioned, earlier.
2014-01-03 20:44:50
Heres another thought; does your state have "classic car" or "collectors car" license plates that exempt you from emissions?

In Pennsylvania, if your car is 15 years or older you can apply for a "Classic Car" license plate. It automatically exempts you from emissions testings, only have to get the safety inspection. I have one, and buncha guys I know in PA have one on their B13's too.
2014-01-04 07:44:23
Originally Posted by ccrelan
Hi Everyone- I tried to get the 1991 SCC project sentra se-r to pass the emissions test today. Unfortunately, I didn't have any luck getting through. Here are the numbers:

HC- reading 38 ppm limit 150 pmm - pass
CO- reading .01% limit .8% - pass
NOx- reading 2512 liimit 1750 - fail

I had a new magnaflow cat installed before the test and the car was plenty warm. I was hoping the new cat would help push things in the right direction.

Does anyone have some recommendations on how to get the NOx down? The rest of the numbers seems good and well below the limit.

Thanks in advance- Cory

Cory - is your SMOG an idle test or a rolling test. Here in California we have a 15 MPH & 25 MPH test. Also if your new CAT has less than 500 miles on it, it too could be your cause thou my initial thought is EGR. Will re-read and re-think in the morning when I have a clear mind.
2014-01-04 14:54:05
The test has the car on rollers, but I am not positive of the miles per hour. I think it was 25 mph if I had to guess. I drove the car about 20 miles after getting the new cat installed. I believe the car has a JDM DE engine in it.

2014-01-05 03:00:22
Thank for the pic - that helps alot.

I would:

Remove the breather and reconnect the proper air hose.
Clean the EGR
Put 200 strong miles on the car

Doing some strong driving prior to performing the test to increase the cats temp can help too or let it idle at 3k RPM for several minutes before giving your smog guy the keys helps (also known as pre-heating the cat).

Last edited by LAM-PARK on 2014-01-05 at 03-02-37.
2014-01-05 13:18:21
what octane gas are you running?
2014-01-05 13:50:29
Originally Posted by ccrelan

I had a new magnaflow cat installed....

High flow cats don't get hot enough. Restrict it on the back end to increase the temps. I learned this trick from Matt Niaura who used it to get though < ..drum roll... > CT emissions. Once you get it passed, remove the restrictor and you're good to go. Try it, you'll see.
Last edited by hammerin hank on 2014-01-05 at 13-51-55.
2014-01-10 00:47:52
UPDATE 1/9- The car passed the retest today with flying colors. I put some more miles on the car the last few days, filled up with high test, added some Startron to the tank, and changed out the plugs. It seems putting some miles on the new cat convertor did the trick. I drove up to Midas in Canton. It is about a 1:15 drive so the car was good and warm by the time I got up there. We had them test the car "as is" and the NOx levels were down to about 700 ppm.

I will be posting some updated pics, info, and plans for the car in another thread here soon. Thanks for all the suggestions.
Last edited by ccrelan on 2014-01-10 at 00-49-09.
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