LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Car failed inspection for emissions.

Thread Tools
 
Search this Thread
 
Old Feb 21, 2007 | 02:26 PM
  #1  
blackwizard22's Avatar
Thread Starter
Teching In
 
Joined: Jun 2004
Posts: 15
Likes: 0
Default Car failed inspection for emissions.

So my 94 lt1 with nothing but a cat back and an intake failed inspection for emissions. The readings were way higher than acceptable. What could be the culprit? Im thinking O2 sensors and injectors migth cure it. thoughts?
Reply
Old Feb 21, 2007 | 02:56 PM
  #2  
BlackScreaminMachine's Avatar
Internet Mechanic
20 Year Member
iTrader: (17)
 
Joined: May 2005
Posts: 9,830
Likes: 2
From: Wallingford CT
Default

So you went on the emissions roller. what were your results and what were the limits.

Often with ODB1 cars you have to pass on the roller. I always put 93 octane with a bottle of rubbing alcohol, run a 180 thermo, change the oil/fuel/pcv filters, do a oil change. Make sure the car is NICE and hot. This should pass.

If at worse change the o2's and replace the CAT, a brand new unbroken in cat will always pass, with your minimal mods.
Reply
Old Feb 21, 2007 | 03:39 PM
  #3  
blackwizard22's Avatar
Thread Starter
Teching In
 
Joined: Jun 2004
Posts: 15
Likes: 0
Default

nox should be 879 but it is 1770. hc reading was suppose to be 117 but it was 2632. my co% rating was suppose to be .65 and it is 2.03. any ideas?
Reply
Old Feb 21, 2007 | 04:33 PM
  #4  
Ralls's Avatar
TECH Fanatic
15 Year Member
iTrader: (32)
 
Joined: Oct 2005
Posts: 1,687
Likes: 0
From: Fairfax, Virginia
Default

I'd say need a new cat. Are you getting really bad gas mileage? Thats a sign of bad o2's. Everything is really high, probably running rich.
Reply
Old Feb 22, 2007 | 02:43 AM
  #5  
SincalT/A's Avatar
TECH Fanatic
iTrader: (16)
 
Joined: Oct 2006
Posts: 1,783
Likes: 1
From: Currently In suspense.
Default

you have more than one problem.for sure cat h.c are way to high and possibly egr not working properly do to the higher flowing exhaust.you need to get the cylinder temps down that will help nox.do you have any other mods no matter how little.
Reply




All times are GMT -5. The time now is 04:03 PM.

story-0
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-1
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-2
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-3
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-4
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-5
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-6
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-7
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-8
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE
story-9
Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

The world was a better place when it was still around.

By Brett Foote | 2026-01-23 09:20:37


VIEW MORE