A few days ago i had my cat taken off my 2001 5.2l as i was driving it i began to notice a popping noise on acceleration and as it is idling (on such as you would hear in a drag car) but i was wondering whether it was an exhaust leak... and to add it is ran off stock headers straight threw to a flowmaster super 40. sounds as if a pop is echoing in the pipe on acceleration, is this normal? Just wanting to make sure everythings right before to muc htime passes where i can get it fixed without charge. Thanks