my 99 rx with about 91k on it seems to make a lot of rumbling/rattling/vibration noises when im parked or stopped at a traffic light. the instant i let off the brake and start moving it goes away. i don't think i have any exhaust leaks or anything like that. the car runs fine otherwise. it just has that old car noise and sound when im stopped. by comparo my 04 tsx with 100k runs silent. i'd like my rx to be the same. any tips? thanks!