Corsa Cat Back and Engine light
Thread Starter
Intermediate
Joined: Jan 2019
Posts: 35
Likes: 6
From: SoCal
Corsa Cat Back and Engine light
So last Friday I swapped my stock exhaust for a Corsa extreme. (cat back)
Today the engine light came on.
Could be a coincidence, but could be something else.
So I was thinking that maybe I need the computer reprogrammed since I changed the exhaust.
What have you guys seen ?
Thanks
Today the engine light came on.
Could be a coincidence, but could be something else.
So I was thinking that maybe I need the computer reprogrammed since I changed the exhaust.
What have you guys seen ?
Thanks
Safety Car
Joined: Mar 2004
Posts: 4,048
Likes: 1,476
From: South Florida
Cactback shouldn't cause a CEL but it can if you have a leak near an O2 sensor or if you tightened the AFM valve modules or NPP valve modules down too tight. They have a resistance area they operate in and if it is too high due to over tightening the small bolts it will throw a CEL. It would be much more helpful to determine the issue if you could get the codes from the ECU.
Thread Starter
Intermediate
Joined: Jan 2019
Posts: 35
Likes: 6
From: SoCal
Code was increased flow at cat, had tech clear it and we will see if it returns.
Talked to shop that installed exhaust and they said they have seen this on other cars where they installed a Corsa system
It usually clears once the computer has sync'd up
Will keep you posted if it returns
Talked to shop that installed exhaust and they said they have seen this on other cars where they installed a Corsa system
It usually clears once the computer has sync'd up
Will keep you posted if it returns
Safety Car
Joined: Mar 2004
Posts: 4,048
Likes: 1,476
From: South Florida
Never heard of increased flow at cat code before. A P0XXX identifier would help.
Also, what exactly did you install? And what exactly did you remove from the car in regards to the exhaust system?
Also, what exactly did you install? And what exactly did you remove from the car in regards to the exhaust system?
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Le Mans Master
Joined: Oct 2014
Posts: 8,672
Likes: 2,726
From: Atlanta GA
Look for exhaust leaks especially if they loosen all your pipes to install and line up the cat back
Also check the rear 02 sensor wires to make sure they are clipped on tight and the wires are not pinched
Lastly make sure they did not break the O2 sensor
No Cat back install should throw a CAT efficiency code and then after reset , set the code again something else is wrong , My bet is one of the wires is off or cut
Dave
Also check the rear 02 sensor wires to make sure they are clipped on tight and the wires are not pinched
Lastly make sure they did not break the O2 sensor
No Cat back install should throw a CAT efficiency code and then after reset , set the code again something else is wrong , My bet is one of the wires is off or cut
Dave
Le Mans Master
Joined: Oct 2014
Posts: 8,672
Likes: 2,726
From: Atlanta GA
Code was increased flow at cat, had tech clear it and we will see if it returns.
Talked to shop that installed exhaust and they said they have seen this on other cars where they installed a Corsa system
It usually clears once the computer has sync'd up
Will keep you posted if it returns
Talked to shop that installed exhaust and they said they have seen this on other cars where they installed a Corsa system
It usually clears once the computer has sync'd up
Will keep you posted if it returns
I might just take it somewhere else as this guy is full of SOUP …..
here is what P420 is and what it means …...has absolutely NOTHING to do with more airflow thru the cat , if anything its less airflow due to a plugged cat or a malfunction with the o2 sensor
https://www.obd-codes.com/p0420
Dave
Safety Car
Joined: Mar 2004
Posts: 4,048
Likes: 1,476
From: South Florida
Burning Brakes
Joined: Oct 2014
Posts: 1,057
Likes: 339
Burning Brakes
Joined: Oct 2014
Posts: 1,057
Likes: 339
The installer likely screwed something up. A cat back installation will not cause these codes. As a matter of fact, the installer had no reason to touch anything upstream from the rear most O2 sensor. You’re getting good advice in this thread. Check your O2 wiring.
The installer had absolutely no reason to touch any of the four O2 sensors. They are not in the way and all of the exhaust to the rear bumper from the mid pipe forward connector is the only thing that they would need to remove, replace or adjust.
Good luck!
The installer had absolutely no reason to touch any of the four O2 sensors. They are not in the way and all of the exhaust to the rear bumper from the mid pipe forward connector is the only thing that they would need to remove, replace or adjust.
Good luck!