L98 failed emissions high CO Help !!
Thread Starter
Burning Brakes
Joined: Oct 2004
Posts: 898
Likes: 1
From: Pearland Texas
L98 failed emissions high CO Help !!
The unthinkable has happened. My beautiful, spotless, 90 just failed emissions. The CO standard at 15mph is .86 I'm at 1.46, at 25mph .94 I'm at 1.55. I just drove the car there, haven't driven it much this week. Any sugsestions ?
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
sounds like you have a vacuum leak or old spark plug wires or it wasn't hot enough, or a lazy oxygen sensor
Last edited by coupeguy2001; Jun 21, 2008 at 11:53 AM.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
It didn't need to have the bejesus run out of it when it was new to pass and if it's right, it shouldn't now. The high CO usually means it's getting too much fuel and scanning it would confirm or rule that out. Assuming you rule it out, it'll need a new CAT. If confirmed, you need to troubleshoot why it's delivering too much gas. So get yourself a scanner so that you can see what it's doing and then post the results. That will eliminate the guesswork or the replacement of good parts - though I have to admit it's sometimes nice to have spares. Otherwise, take the collective guesses and flip a coin as to which one you want to try first.
Thread Starter
Burning Brakes
Joined: Oct 2004
Posts: 898
Likes: 1
From: Pearland Texas
OK, my first thoughts were correct. The inspector lady couldn't get the parking brake off, the hood open. So I stood there and watched her. The RPM cable, she connected to the throttle cable. I mentioned that, and since I couldn't see from my side of the red line she connected it to number three instead of number one. The whole time the car wasn't running. There were online problems, purging problems, everything was stacked against me. Finally after 30 minutes she started it up and the RPM's were wrong, disconnected and bypassed. She ran it thru the gears like crazy and was in 4th gear for the 25 mph test. Hell the car was hardly running. Thanks to everyone for advice, I ran it hard and on the freeway and went back and their machine was down. Pitched a fit and got my money back, went down the street and the old guy says" It need to be hot". BINGO. Thanks to all.
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