high idle after warm up

my 93 gt sl idles high after engine temp is at normal range. Tried to adj. base curb idle per manual, but no help. Removed the throttle body and cleaned carbon from isc area, throttle plate, base idle set screw. also removed the fast idle control valve housing and cleaned valve. Idle with ac off is @1500, a/c on drops to 1100. When i try to adj. curb ible with pin 10 and brown connector grounded, i can turn the base idle set screw in to the full closed position, but the engine will not stall.It does not have hardly any effect on idle set. Mayby i have a bad fast idle control valve. Any help with tring to adjust idle is needed. thanks

notice on the back side of the throttle body where the spring thing is. theres a bolt there with a nut u can loosen up or tighten. loosen or tighten that to where it will make the throttle body more open or closed. thats what i did to control my high idle. i hear that that screw ur talking about isnt meant for controlling the idle.

notice on the back side of the throttle body where the spring thing is. theres a bolt there with a nut u can loosen up or tighten. loosen or tighten that to where it will make the throttle body more open or closed. thats what i did to control my high idle. i hear that that screw ur talking about isnt meant for controlling the idle.
StealthModifier that screw you adjusted is not meant to adjust the idle. It is not meant to even be adjusted. I got some driveability issues with my car because my dad messed with mine at one time. Also I have controlled the idle with my BISS on a number of occasions.

asatech it sounds to me like your iac may be faulty. When mine was dying somedays it would idle extremely high and other days it would want to stall. I bought a used one off the board and its been fine since.

i got in my car today an the car was idling at 800 an dropping to 400 an kept going up an dropping down. i ended up adjusting the biss screw so it idles at 900 an it didnt drop. the car for some reason drove a lot better too.

The hunting idle could very well be from you adjusting the SAS screw. My car still idled messed up after I got my "new" ISC. I found out about the SAS and how its not supposed to be adjusted. I put it back in spec and the car has been perfect since.

my car as always idled wierd. not that the rpms raise an drop. its like it builts up pressure an puts a little bit, an the pitch constantly get lower an higher. but i guess the reason is since i dont have a muffler.