I drive a 96 mustang,and was told that the 1990-2000 model's body is made from sheet metal and on bumps,or a dirt road it will make rattling sounds. Your exhaust pipe is another explanation if it is loose.
Sounds like a loose electrical connection, possibly a loose ground.
loose belts
Sounds like your problem is probably a loose heat-sheild or a loose exhaust. Have it checked.
Possible loose exhaust pipe, check hanger clamps.
Tire out of balance, bent wheel, loose wheel bearing, defective tire, loose wheel lug nuts, & worn steering or suspension parts.
It sounds like either a loose ground or power supply, start by checking the connections at the blower motor............
That sounds like a broken or loose strut assembly.
This sounds like something loose underneath that rattles only at a certain vibration level while accelerating. I would get underneath the car when cold and see if pushing on the various heat shields or muffler components shows a loose connection. Often times a heat shield can be pushed just a small way towards a muffler pipe and cause this problem.
Sounds like the alternator has failed and you ran the vehicle until the battery was drained.
Check your front bumper, it might be loose, or the radiator fan might me hitting the case, or all your nuts are loose and its about to fall appart :P Could use more info like when does it vibrate, at a stop, driving along slow, driving along fast or braking.
Many time the high pitched whistle will be cause by a loose or unattached vaccuum line on the engine.
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