Ive just put in a Cat back exhaust recently 2 days ago, and its standard everything even the cat and dump...I dunno if its running rich or anything but definitely its not backfiring cuz the exhaust underneath the car goes "POP!" occassionally and pretty often when i drive even normally...Occurs randomly but more often when i let go off throttle, but i can assure you the sounds not coming from the back of the exhaust tip...its somewhere around where the cat is underneath the car.
What could it be guys?? im very irritated...Did i blow something?