Recently after running at the local drags I heard an exhaust leak when I BACKED UP and now it also makes noise when accel. hard. I can hear it coming from around the flex pipe and cat connection (I think). Possible senario are motor mounts need replacing and caused flex pipe damage....I checked the engine movement and it does'nt appear excessive but it does move a little in each direction when put in and out of D and R (yes its atx). Could exhaust escape from the "flex " part of unit if stressed?