How/where do I look for an exhaust leak on HHR 2008? on 2008 Chevrolet HHR

Car lacks power and takes its time to catch its speed. Makes grumbling sound? How can I find the leak?

Asked by for the 2008 Chevrolet HHR
normally around leak area there will be blk carbon build up. look at exh system for that or listin with a pcs of tubing.