Inefficient Corsa Cats Code
Thread Starter
Intermediate
Joined: May 2008
Posts: 30
Likes: 0
From: Linden NC
Inefficient Corsa Cats Code
I just bought a 2007 coupe that has a complete Corsa exhaust from the manifold back. I need to get the NC state inspection done, but the CEL is on. I took it to a local dealer who said it was throwing an "inefficient cat" code. Is there a way to tune this out so I can get it inspected or do I need to get rid of the high flow cats? When I had the CEL reset at the dealer it just popped up again three days later. TIA, Greg
Safety Car
Joined: Feb 2007
Posts: 4,939
Likes: 448
From: CHOCOWINITY NC
You can tune it out...I unchecked the rear CAT reporting in HP tuners and just flew through NC state insection. Just make sure all your other readiness codes are set..
LG pro's, High flow cats and a Tune
LG pro's, High flow cats and a Tune
Safety Car
Joined: Feb 2007
Posts: 4,939
Likes: 448
From: CHOCOWINITY NC
Melting Slicks
Joined: Feb 2004
Posts: 3,307
Likes: 110
From: Tucson AZ
Hi Flow cats setting code
You can also buy the Diablo Sport Predator hand held tuner and do it yourself.
Some Predator handheld models have the capability to turn off the cat codes built in, on others you will have to email your current tune to one of the guys at Diablo and he will mod it and return it to you and then you can load it.
What happens is the original cats are right up against the cast iron manifold so that they can heat up to the "light off" temp much quicker. Your new hi-flow cats are down in the X pipe and take longer to come up to "light off" temperature. The ECM periodically runs a check on the O2 sensors checking the output of the front O2 sensor verses the rear O2 sensor. The front sensor is in front of the cats and shows a variable amount of O2 while the rear is behind the cats and should be flat signifiying the exhaust is clean. If the hi-flow cats have not reached "light off" temp, both O2 sensors will vary and this sets a code that tells the technician the cats are not working.
Some Predator handheld models have the capability to turn off the cat codes built in, on others you will have to email your current tune to one of the guys at Diablo and he will mod it and return it to you and then you can load it.
What happens is the original cats are right up against the cast iron manifold so that they can heat up to the "light off" temp much quicker. Your new hi-flow cats are down in the X pipe and take longer to come up to "light off" temperature. The ECM periodically runs a check on the O2 sensors checking the output of the front O2 sensor verses the rear O2 sensor. The front sensor is in front of the cats and shows a variable amount of O2 while the rear is behind the cats and should be flat signifiying the exhaust is clean. If the hi-flow cats have not reached "light off" temp, both O2 sensors will vary and this sets a code that tells the technician the cats are not working.
