The noise could be a bushing or something making the noise when the car rocks. I don't feel that a trans mount. That could make a clunk, but not cause the car to rock. As far as the high idle, again, you would need to keep your foot on the brake, but no rocking. I feel the idle is going up and down. There is an idle air control valve that is designed to keep the idle steady. If bad, one of the most likely symptoms is an idle that goes up and down. Thus, you get a surge in the engine which while stopped can cause the vehicle to rock. It could also be something as simple as a vacuum leak. If the car runs good once moving, the IAC is the first thing I would check.
Saturday, September 17th, 2011 AT 4:53 AM