Check Timing First Sounds Like That Is Your Problem. If it turns out to not be the ignition timing, it could also be the camshaft timing. If your camshaft is mistimed it means that your timing chain or timing belt has slipped and must be replaced.
Dirt in the carb or carb out of adjustment or both.
If it is throtle body equipped, the idle control s solonoid controls it. If it has a carb there is an adjustment screw on the bottom of the carb.
May have an idle solenoid on the left side of carb.
There should be an idle setting on the side of the rochester carb.
On the side of the carb.
there is a little screw on the back of the carb. if you loosen it, it will idle slower, tighten it, it will idle faster.
check the ait. on yhe left side of carb..it control's idle.
Right at the top of the engine you will find the carb immediatley to the right on the carb you will see a flat head screw this will adjust your idle , helps to have a second person on this.
twist the screw under the carb
adjust your idle screw on the side of the carb its the one with the spring on it. if that doesnt help then take the carb apart and clean it to make sure theres no dirt in it.
I assume it has carb's. If so, follow the cable to the carb's. There is a little screw you can tighten to increase the idle or lower it. Just a long screwdriver and watch the tach.
adjustment screw is between throttlre linkage and carb body on the right side of the carb as you stand at the front of the car looking at the carb