I have a 1994 Saturn S.W, automatic. It runs fine, but when you are driving with very little pressure on the throttle, it shakes like a bucking bronco. It seems to be mechanical rather than electrical and never happens under acceleration/deceleration. I don’t even think of drinking coffee while driving.sha
Bad throttle position sensor? Does vehicle speed make any difference?
Not a bit, it does it slow, it does it at freeway speeds. Always when your foot is only lightly on the throttle. If you accelerate or decelerate even slightly, it won’t shake a bit. Its driving me nuts.
You might consider the engine mount on the top/right front - very typical to fail. Local parts store about $35.
While this may sound a bit strange, I have run across a couple of vehicles in the past that exhibited this trait and it was due to corroded terminals on (depending on the type of vehicle) the ignition coils or distributor cap.
A heavy layer of whitish looking corrosion can build up on the terminals and cause this problem. It’s easy to cure if this is the case. Simply disconnect the plug wires at the coils and if they’re corroded over clean the plug wire ends and coil terminals with a distributor terminal brush. (available at any parts house cheap)
Not saying that is even your problem but it’s easy to check and easy to fix if it is.
Hope that helps.