About to give up...

[Mark B]

Hey guys,
Still on my quest to pass the NOx portion of the emissions test. I am currently double what the limit is. I have heard that the EGR system needs a little exhaust backpressure to fuction properly. I wonder if I have too little backpressre for it to work right. LOOK at my Sig for my mods.

This is what I have done so far:
-NEW EGR Valve
-NEW Plugs
-NEW Wires
-NEW 02 Sensor
-NEW Distributor Cap
-NEW Rotor
-NEW Vacum ines
-NEW Catalityc Converter
-CLEANED EGR passages
-SET timing at all different locations (NO HELP)
-SET fuel pressure at all different levels (NO HELP)
-CHECKED for vacum @ EGR valve (15inches during operation)
-ALWAYS ran premium fuel


What do you guys think? Is there some other avenue that I havent tried? How about the backpressure thing? Does that sound like a good idea?

[Jeff_in_Atl]

In Georgia, if you prove that you have spent X amount of money to get a car to pass emissions and it still doesn't pass, they have to give you an exemption.

[Squat13]

Just move to flordia, We dont give a heck!

[SteveH95Formula]

You catilytic converter may not be up to standards. It might be a high flow performance unit but not as good emision wise as the stock converter. Just my guess.

[Christopherrr]

In Georgia, if you prove that you have spent X amount of money to get a car to pass emissions and it still doesn't pass, they have to give you an exemption.

that was what I was thinking when I read your post...see if they won't exempt you...

[Mark B]

Jersey has that too...

But only if a registered shop does the repairs. I have been doing all of the repairs so far. Its been pretty much a guessing game the whole time. I am running out of ideas though. I may have to pay a shop to fix it. (I HATE BEING POOR!!)

[Kevin - Blown 95 TA]

Try a gallon of denatured alcohol in 8 gallons of premium. If that doesn't do it, you might need a new cat. Also the EGR needs to work, you can't be running lean or too hot, can't have low octane - those will raise NOX.

Oh yeah - like was mentioned, aftermarket cats chince on the Paladium, Rhodium, and Platinum because they are expensive metals, and they only need to wty for 2 years as opposed to the OEMs who wty for 7-10 years. Good aftermarket converters include Walker & Brown. They are more like OEM, but do have some hi-po models. When my car failed twice with the Random cat, I cobbled the stock unit on there and passed with 2x better NOX, 5x better HC and 10x better CO.

[4THGEN Z]

When my car failed twice with the Random cat, I cobbled the stock unit on there and passed with 2x better NOX, 5x better HC and 10x better CO.

Wow, Randon tech cats aren't cheap either!!

[Kevin - Blown 95 TA]

Wow, Randon tech cats aren't cheap either!!

And the stock unit had 17k mi and 5 years compared to the Random cat with 3k mi and less than 2 years on it. They warrantied me a new one, but the thing inside came loose and rattly this summer so I punched it out with a pipe! Not what I wanted to do, but I'm sick of messing with it.