I had a shop install a borla cat back and had no problems for a week. I have only driven it twice since then and it has been fine. I got into it today and I have a check engine light on. What are some possibilities for this? I am assuming an O2 sensor issue, but I could be wrong.

 

The cat-back shouldn't have thrown a CEL.
Take it to Autozone and get the code pulled.

 

check your gas cap, it's not on tight.

 

for real......the gas cap...if thats it i will kick myself in the nuts....i will go check it now

 

can't be the gas cap. could be the gas cap.
you can go to an Autozone and have them pull the code to be sure...

 

I think you meant to say, "can't be the CAT BACK. could be the gas cap."
Or were you playing Jedi mind tricks again.

EDIT: If you got the CEL as soon as you started the car, its the gas cap.
Just give the gas cap a couple more turns and allow a few drive cycles to clear the CEL.

 

say what?

 

not the gas cap

 

could be the gas cap. lol

happened to me.....

 

Just re-set the ECU

If it comes back you have a problem.

 

Last time I encountered the gas cap CEL I couldn't clear it with the odometer and brake pedal dance reset.
I had to wait for a couple drive cycle to let it clear itself.

 

thanks for the input.....i guess i will wait and see after a few drive cycles. if that doesnt work i will reset the ECU