Make sure throttle returns fully to its stop, and hits the isv microswitch everytime also. As said clean three temp sensors up, they have blue/white, green/red and red/yellow wires going to them. Make sure isv buzzes on ignition, and carb clean it out. If all this is good, remove idle screw from throttle body, clean with scotchbrite and check o-ring condition, then screw it back in and unwind it to raise tickover to 1000 rpm +/- 50rpm