Emission Test Failed! - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Reply
 
 
 
Thread Tools Search this Thread
Old 03-31-2006, 05:36 PM   #1
Senior Member
Posts like a Turbo
Thread Starter
 
Join Date: Jul 2003
Location: Markham, Ontario, Canada
Posts: 239
Thanks: 0
Thanked 0 Times in 0 Posts
faisalmali is on a distinguished road
Default Emission Test Failed!

These are the results:

ASM 2525 Curb Idle


Limit Reading Limit Reading
HC ppm 57 19 200 9
CO% 0.32 0.00 1.00 0.00
NO ppm 421 639 N/A N/A


I put brand new NGK TR55 plugs. Cat is 2 years old (passed last emission on the same one) - it is a Walker generic one. Excellent CO% and pretty good HC reading suggests to me that it is not cat. O2 is about 3-4 years old. It is a Neihoff. Could it be a problem?

The only MIL code that I get 56 intermittently, which I think relates to BCS. The little lever that is attached to the supercharger does stick (doesn't go down completely), but would that cause emission issue, though?

Guys, I need to get this car to pass in 7 days (it'* on temp permit). How do I go about troubleshooting this?

Thanks.
faisalmali is offline   Reply With Quote
Old 03-31-2006, 06:36 PM   #2
Senior Member
True Car Nut
 
Join Date: Oct 2002
Location: Groton, CT _NEBF 05, 06, 07_
Posts: 2,703
Thanks: 0
Thanked 0 Times in 0 Posts
markwb is on a distinguished road
Default

It looks like it failed on the Nitrous Oxides, correct? Is the cooling system in good order. May need a real good coolant flush to help things out. Not sure about the cat. Some other GH'* will be in here directly.
markwb is offline   Reply With Quote
Old 03-31-2006, 06:41 PM   #3
Senior Member
Posts like a Turbo
Thread Starter
 
Join Date: Jul 2003
Location: Markham, Ontario, Canada
Posts: 239
Thanks: 0
Thanked 0 Times in 0 Posts
faisalmali is on a distinguished road
Default

Quote:
Originally Posted by markwb
It looks like it failed on the Nitrous Oxides, correct? Is the cooling system in good order. May need a real good coolant flush to help things out. Not sure about the cat. Some other GH'* will be in here directly.
Yes, it failed on NOx. I just did my waterpump so coolant was replaced. I have the stock 195 degree thermostat. Should I toss in a 180? I don't want to jeopardize the HC'* though.
faisalmali is offline   Reply With Quote
Old 03-31-2006, 07:20 PM   #4
Senior Member
True Car Nut
 
Join Date: Jul 2004
Location: Twin Falls, Idaho
Posts: 7,545
Thanks: 0
Thanked 1 Time in 1 Post
Hans is on a distinguished road
Default

what sort of MPG numbers are you pulling?
Hans is offline   Reply With Quote
Old 03-31-2006, 08:19 PM   #5
Senior Member
Posts like a Turbo
Thread Starter
 
Join Date: Jul 2003
Location: Markham, Ontario, Canada
Posts: 239
Thanks: 0
Thanked 0 Times in 0 Posts
faisalmali is on a distinguished road
Default

Pretty crappy, actually. Like 13 or 14 mpg. You're thinking replace the O2?
faisalmali is offline   Reply With Quote
Old 03-31-2006, 08:22 PM   #6
Senior Member
Posts like a Corvette
 
Join Date: Jun 2005
Location: Berkeley, IL
Posts: 1,596
Thanks: 0
Thanked 0 Times in 0 Posts
DarkShadow is on a distinguished road
Default

Quote:
Originally Posted by faisalmali
Pretty crappy, actually. Like 13 or 14 mpg. You're thinking replace the O2?
replace the o2 with an acdelco one, a good source for them is gmpartsdirect.com or rockauto.com

and if i recall correctly the egr valve can cause high nox emissions, maybe giving it a quick clean up might help
DarkShadow is offline   Reply With Quote
Old 03-31-2006, 11:56 PM   #7
Senior Member
Posts like a Turbo
Thread Starter
 
Join Date: Jul 2003
Location: Markham, Ontario, Canada
Posts: 239
Thanks: 0
Thanked 0 Times in 0 Posts
faisalmali is on a distinguished road
Default

Will do. Would the EGR not throw a code, though?
faisalmali is offline   Reply With Quote
Old 04-02-2006, 05:29 AM   #8
Senior Member
True Car Nut
 
GAMEOVER's Avatar
 
Join Date: Aug 2003
Location: Racine Wi
Posts: 5,146
Thanks: 0
Thanked 0 Times in 0 Posts
GAMEOVER is on a distinguished road
Default

replace the BCV
GAMEOVER is offline   Reply With Quote
Old 04-02-2006, 11:33 AM   #9
Senior Member
Posts like a Turbo
Thread Starter
 
Join Date: Jul 2003
Location: Markham, Ontario, Canada
Posts: 239
Thanks: 0
Thanked 0 Times in 0 Posts
faisalmali is on a distinguished road
Default

Quote:
Originally Posted by GAMEOVER
replace the BCV
To confirm, you mean the BCS, right? Thanks.
faisalmali is offline   Reply With Quote
Old 04-02-2006, 11:43 AM   #10
Senior Member
True Car Nut
 
GAMEOVER's Avatar
 
Join Date: Aug 2003
Location: Racine Wi
Posts: 5,146
Thanks: 0
Thanked 0 Times in 0 Posts
GAMEOVER is on a distinguished road
Default

Quote:
Originally Posted by faisalmali
Quote:
Originally Posted by GAMEOVER
replace the BCV
To confirm, you mean the BCS, right? Thanks.
the boost control valve is the black plunger with the arm on it which you stated sticks?

the boost control solenoid is the is right next to the black plunger with a vacuum line going to the plunger
GAMEOVER is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Passed Emission test with Flying Colors! azu General GM Chat 1 11-24-2007 11:20 PM
emission inspection test result report aukc General GM Chat 7 03-07-2005 08:30 AM
HELP WITH EGR !!! failed emission Drifter420 1992-1999 30 04-21-2004 12:23 PM
emission test with S/Cless Drifter420 1992-1999 10 03-24-2004 04:15 PM
bonnie failed the nox in emission test rrrddgy 1992-1999 4 03-01-2004 02:21 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 12:41 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.