Failed Smog
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TECH Resident
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Joined: Feb 2004
Posts: 888
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From: Simi Valley, CA
Failed Smog Well I went and smogged my car today. The first time he put it on the machine the car failed, he then let idle for a few minutes before trying again and I barely passed the second time around. These are my results
At 15 mph: PASSED
%CO2 Meas = 14.53
%O2 Meas = 0.29
HC (PPM) MAX 51, AVE: 9, MEAS 12
CO (%) MAX: 0.48 , AVE: 0.02, MEAS 0.05
NO (PPM) MAX 419, AVE 57, MEAS 418
At 25 mph: PASSED
%CO2 meas = 14.50
%O2 meas = 0.21
HC (PPM) MAX 35, AVE: 7, MEAS 11
CO (%) MAX: .46, AVE: 0.03, MEAS 0.04
NO (PPM) MAX 706, AVE 50, MEAS 394
Any guesses why I got 418 NO (PPM) at 15MPH?
This is all the stuff Ive done to the motor
- K&N Air Filter
- Whisper Carbon Fiber Intake Lid
- Smooth Intake Bellow
- Ported and Polished Throttle Body
- MSD Wires
- NGK TR55 Spark Plugs
- 3" Exhaust Cutout
- Magnaflow Exhaust
- LS7 Lifters
- Comp Cams LSX Chromemoly Hardened 7.400" Pushrods
At 15 mph: PASSED
%CO2 Meas = 14.53
%O2 Meas = 0.29
HC (PPM) MAX 51, AVE: 9, MEAS 12
CO (%) MAX: 0.48 , AVE: 0.02, MEAS 0.05
NO (PPM) MAX 419, AVE 57, MEAS 418
At 25 mph: PASSED
%CO2 meas = 14.50
%O2 meas = 0.21
HC (PPM) MAX 35, AVE: 7, MEAS 11
CO (%) MAX: .46, AVE: 0.03, MEAS 0.04
NO (PPM) MAX 706, AVE 50, MEAS 394
Any guesses why I got 418 NO (PPM) at 15MPH?
This is all the stuff Ive done to the motor
- K&N Air Filter
- Whisper Carbon Fiber Intake Lid
- Smooth Intake Bellow
- Ported and Polished Throttle Body
- MSD Wires
- NGK TR55 Spark Plugs
- 3" Exhaust Cutout
- Magnaflow Exhaust
- LS7 Lifters
- Comp Cams LSX Chromemoly Hardened 7.400" Pushrods
Last edited by uLs1a; Jul 30, 2009 at 05:43 PM.
Wow, i would of thought you passed with no problem, I have Mid length headers and catted Y with bolt ons, pretty much the same as you and had no problems, I failed the Visual but i only did it to get base decals. Could you need a tune??
A few things I always do, Good grade of gas (Chevron), change the oil and make sure the Cat is as hot as you can get then. I drive in a lower gear on the way to the testers shop to keep the RPM higher to assist in heating up the Cat's. Might check your O2's.
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From: Western Burbs of Detroit
Your motor is basically stock, running on a factory tune correct ?
Why are you using ngk 55's ? Isn't that a cooler plug used in higer compression motors to help prevent pre Detonation ?? Correct me if I'm wrong.... Get her tuned to make sure you aren't running pig rich too. A ported tb could be part of the problem too since its untuned. Just my 2 cents. Good luck !!!
Why are you using ngk 55's ? Isn't that a cooler plug used in higer compression motors to help prevent pre Detonation ?? Correct me if I'm wrong.... Get her tuned to make sure you aren't running pig rich too. A ported tb could be part of the problem too since its untuned. Just my 2 cents. Good luck !!!
Thread Starter
TECH Resident
iTrader: (22)
Joined: Feb 2004
Posts: 888
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From: Simi Valley, CA
Its not the p/p throttle body cause I have been running that for a good 5 years. NGK TR55 is what a lot of people on here reccommend and I have never had a problem with them before. I believe the NGK TR6 is used for fi and n02.
The only SES code I have had was P0174, but that was a good two months ago
The only SES code I have had was P0174, but that was a good two months ago
Thread Starter
TECH Resident
iTrader: (22)
Joined: Feb 2004
Posts: 888
Likes: 1
From: Simi Valley, CA
I mean I passed the second time around so Im not worried about since I dont have to do it for another 2 years. Just wanted to know what people thought of what made me fail the first time
