Is the rattle coming from underneathe the car? Or under the hood?
If underneathe the car, raise it on a lift and have someone to rev the engine as you and a partner looki for the sorce of the noise.
Things to check;
The metal cover to the catalytic converter.
The heat shield above the exhaust pipe (they attach to the bottom of the floor board)
Engine and transmission mounts
Exhaust pipe hangers
Wednesday, July 24th, 2013 AT 11:35 AM