Vacuum leak is one cause.
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Another possible cause may be a bad Idle Air Control Valve (IAC Valve).
Your car should Idle, once the engine is at operating temperature, between 680-750 RPM. If the engine idles below this range with no appliances on, i.e. Air Conditioning, Fan or Window Heat, then your IAC Valve may have gone bad.
SUBMITED: Friday, 03JUN11
Yes, either can cause a shake while driving.
Sisters - Idoling album - was created on 2011-03-16.
Nope.
miss alignment of tires
If your car shakes while underway, your tires have worn incorrectly from misalignment. If it shakes while in park or not moving, your engine is misfiring.
have you tried to get your wheel realigned
Normally this is caused by warped brake rotors.
there a lot of things, the main ones are lack of air, and the spark plugs need replacing.
rubber bushings in motor mount worn
Check all rubber hoses near manifoil, than check manifoil gasket and carb body gasket, If all fails check flange or converter, than check idle jet and switch in carb.
Sounds like wheel imbalance or possibly a bad wheel bearing(s).
Loose motor mounts.