Quote: It is used to set engine idle RPM. Chrysler had a run on issue, I can only assume, so the easiest/cheapest way to fix it is to have the butterflies closed completely when you shut off the engine. The solenoid is powered up when you turn on the key and it open the butterflies, it is what you are supposed to adjust to set idle speed.
With a 4 speed car I have always gotten in the habit of slightly leaving the clutch out as I am turning the ignition off. (Kind of like stalling the car out by leaving the clutch out too fast and not giving it any gas). This will not allow the motor to keep running after you turn the ignition off.
If this is all the idle solenoid does, then I cannot see spending the extra money for it.
