Failed Emissions...Again
Thread Starter
On The Tree
Joined: Jul 2005
Posts: 187
Likes: 0
From: Gilbert, AZ
Failed Emissions...Again I just love living in Arizona. On any given day you can see numerous rattletraps with Sonora or Chihuahua Mexico license plates belching smoke, yet, I live here and I go through grief trying to get my car to pass emissions. C'est la vie... Markus plays by the rules, so be it.
It failed the first time, took it to the mechanic and he said the cat was bad; no problem, new cat, and back we go. This time it passed everything but failed the NOX by .07. A couple of things on the retest: their equipment needed 'recalibrating' so the car had to sit there, shut off, for about 15 minutes. I believe that having a car fully warmed up will test better, I wonder if that did it or, I noticed my air filter cone (K&N) had (again) fallen off.
Any advice or helpful suggestions is appreciated.
Additional cliff's notes: car is a 94 Z28 M6, no SES, the only mods are a CAI, TB bypass and an aftermarket exhaust, 128K; I was running mid-grade fuel, not premium, right before the test I took a 20-mile jaunt on the freeway to get the car good and warmed up.
It failed the first time, took it to the mechanic and he said the cat was bad; no problem, new cat, and back we go. This time it passed everything but failed the NOX by .07. A couple of things on the retest: their equipment needed 'recalibrating' so the car had to sit there, shut off, for about 15 minutes. I believe that having a car fully warmed up will test better, I wonder if that did it or, I noticed my air filter cone (K&N) had (again) fallen off.
Any advice or helpful suggestions is appreciated.
Additional cliff's notes: car is a 94 Z28 M6, no SES, the only mods are a CAI, TB bypass and an aftermarket exhaust, 128K; I was running mid-grade fuel, not premium, right before the test I took a 20-mile jaunt on the freeway to get the car good and warmed up.
Why weren't you running premium fuel? Use up your gas tank as much as possible and fill up with premium. Also check your oil... if it's dirty or if you put a low grade, it adds to emissions. And definitely go for a 20 minute drive again. There will be less emissions once it's fully warmed up. You can even try checking an auto store for a fuel additive that reduces emissions. I haven't looked into it, but it can't hurt.
nox is caused by high combustion temps. im assuming you still have the egr system hooked up, which is responsible for keeping nox in check. if the car was shut off it could have been heat soaked. make sure the car is at operating temps and that they turn the fan on in front of your car.
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TECH Enthusiast
Joined: Feb 2006
Posts: 517
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I had the same problem with NOX.
I changed the fuel filter and put some fuel additive called Gaurented To Pass in the fuel tank and ran it through a tank of gas.
then i went to chevron and filled here up with 91 octane the best here in CA and she passed.
try it i bet u will pass
I changed the fuel filter and put some fuel additive called Gaurented To Pass in the fuel tank and ran it through a tank of gas.
then i went to chevron and filled here up with 91 octane the best here in CA and she passed.
try it i bet u will pass
I think emissions testing a car over 15 years old is just plain stupid. Saftey and visual, thats it.
From my experience, thats a 100% correct. One year they let my car sit for about 45 minutes, then put it on the machine right after they sarted it up, barley passed. How ever the last 7, so long as the cars been at operating temp, passes by miles. The O.E design these cars to be tested at normal operating temps for emissions for a reason.
From my experience, thats a 100% correct. One year they let my car sit for about 45 minutes, then put it on the machine right after they sarted it up, barley passed. How ever the last 7, so long as the cars been at operating temp, passes by miles. The O.E design these cars to be tested at normal operating temps for emissions for a reason.
Thread Starter
On The Tree
Joined: Jul 2005
Posts: 187
Likes: 0
From: Gilbert, AZ
Failed Emissions...Again ** Update ** Well, a can of G2P didn't help, a new EGR didn't (although it reduced the hydrocarbons by a considerable amount) and it still was failing the NoX (just barely).
Thankfully, AZ has a law that after spending X amount of $ you can apply for a one-time waiver provided you're not bombing the test too badly (and you pass the cat visual inspection). So, $15 for a waiver, I'm good to go for another 2 years now. To celebrate, I opened up the cut-out and proceeded to annihilate a 1/2 acre of Amazon rainforest and put a couple of divots in the ozone layer.
Thankfully, AZ has a law that after spending X amount of $ you can apply for a one-time waiver provided you're not bombing the test too badly (and you pass the cat visual inspection). So, $15 for a waiver, I'm good to go for another 2 years now. To celebrate, I opened up the cut-out and proceeded to annihilate a 1/2 acre of Amazon rainforest and put a couple of divots in the ozone layer.
Last edited by azmarkus; Mar 27, 2009 at 05:10 PM. Reason: Gargled syntax
I just had to get mine done since it just came out of storage. I was worried since i have a slight miss that it was going to run slightly richer then normal. I just put that as said earlier "guaranteed to pass" stuff in the tank and drove around for about half hour or so and then went in and crossed my fingers that it would pass. My numbers were actually pretty respectable non of the readings were really close to the limits. Either my engine is running is really good shape or that additive works wonders. My car has 210,000km on it so you see why im worried.
Bad cats and o2 sensors will definetly kill your etest so new ones would really help make your car pass. I would also suggest the additive as it cant hurt and only costs of what $10. Its either $10 or spend alot of money of other **** trying to get it to pass specially if its close.
Bad cats and o2 sensors will definetly kill your etest so new ones would really help make your car pass. I would also suggest the additive as it cant hurt and only costs of what $10. Its either $10 or spend alot of money of other **** trying to get it to pass specially if its close.
To celebrate, I took the opened up the cut-out and proceeded to annihilate a 1/2 acre of Amazon rainforest and put a couple of divots in the ozone layer.[/QUOTE]
LMAO!!!!!!!!!!!!!!!!!!!!!!!! I drive around with mine open as much as I can. I want global warming to get rid of the 4' of snow we have here in the winter..LOL I want palm trees....
LMAO!!!!!!!!!!!!!!!!!!!!!!!! I drive around with mine open as much as I can. I want global warming to get rid of the 4' of snow we have here in the winter..LOL I want palm trees....
I find it funny that you have to go thru some stupid hoops(like driving your car around to "warm up") for it to pass emmissions. They should really change the way or what they test for.... makes me glad I live in a non emission state.... 
Although I have been thinking about moving to Texas....
