[Sam Tango]

I hear a clunk from the rear when going over bumps;

This is a new car (2023 LCI) and is stock other than AWE exhaust, what could cause this? The exhaust is mounted solid and the dealer did not find any problems with the suspension.

My theory is; the valve actuator which is tucked behind the heat shielding when installing the new exhaust is jumping around in there.

[prostcfc]

Originally Posted by Sam Tango

My theory is; the valve actuator which is tucked behind the heat shielding when installing the new exhaust is jumping around in there.

Quite possible. I'd open up the heat shield and wrap the actuator in something temporarily to see if it goes away.