Now I don't remember when this started. I think it was after the dealership replaced the motor mount thinking it was the cause of a different noise. It also could have been when the MyMINI exhaust was put on. So far no one has had a MyMINI exhaust rub so I don't believe it is that. But after all that I had a pulley installed at Helix so all of that was taken apart and tightened up anyway.

All I can say is its a thunk that can only be heard with the windows down and only happens some of the time. It is one thunk, one hit, going over a bump. It sounds like a solid/metal type sound. It doesn't rattle or keep hitting, just hits once. It sounds like it is coming from underneath the car, towards the front/middle.

Anyone had something similar? Any way of describing what hitting of the heat shielding sounds like?