Okay so i have a 2003 monte carlo ss that i installed an aftermarket exhaust along with a downpipe from zzperformance. Since the install the car has made a high pitch whistle/whine on acceleration(between 4000rpm-5000rpm only). Ive checked for leaks along easy access areas on the exhaust. Wondering if anyone else had this issue. Will also mention that it dose have a cold air intake from the same company if that matters at all.