i installed a jdm header along with a brand new carsound cat 4 days ago... well today as i was driving my check engine light came on and it was cel 67..which is catalyst..my cat cant be bad because it was brand new. what can it be? i doubt it can be a faulty 02 sensor cause that would throw another code. could it be that since im a obd2 and having a high flow would cause this? would a 02 simulator fix this. any advice thanks

99 gsr basic bolt ons

 

Yeah the O2 sensor thinks your cat is not lighting off excess fuel. The car will drive fine. Don't know about the simulator thing, sorry.

 

bump..anyone else