997.1 C2S - Chirping Metallic Sound at 3,200 RPMS

[War584]

I recently bought a 2006 C2S with 55K miles on it. The car makes a high pitched metallic chirping sound consistently at 3,200 rpm and 4,500 rpm when the car is warm. It only makes the sound while driving or shifting but not from 1st gear and not while rev'd without load. The sound will continue going if I keep the rpms on that number. I had the water pump replaced but the sound continues.

The car has a factory sport exhaust - when the sport exhaust is turned on the noise is not as consistent. Turned off it is consistent. The prior owner had the sport exhaust disconnected so the sport feature was always on. I had his mechanic reconnect it before purchasing the car.

My mechanic checked out the exhaust brackets, connections, tail pipes, heat shields and anything else that could make a noise or high pitched metallic sound but he could not find the source of the noise. He thinks it is exhaust related. I'm thinking possibly inside the sport exhaust or related to the reconnection.

Thoughts or suggestions before I take it to another shop? Thanks.

[looneybin]

i have PSE also and had a chirping sound when decelerating
turned out to be loose baffles inside the muffler cans.
I had a welder cut open the cans and tack weld the baffles, then weld the cans back together
no more chirp