I assume the discussion is regarding the stock 2.8-V6 Fiero?
I remove the IAC using 2 adjustable wrenches, since I don't have a socket big enough. I first unplug and remove the TPS. Then unplug the IAC. Then put adjustable wrench on IAC at 90 degrees to where you would normally place it. Use the other adjustable wrench to turn the 1st wrench. It turns only about 1/8 of a turn, given all the obstructions, but it's enough.
Cleaning the IAC itself, spray using carb cleaner, but hold IAC, needle down, so carb cleaner does not get up inside the solenoid section. That must stay free of that type of solvent. If you want to clean the solenoid section, spray using electronic cleaner, sold in Radio Shack. Clean needle tip with carb cleaner and tissue.
Adjust IAC so tip of needle is 1.125" from it's gasket seating position. On OEM style IACs, place valve in a vise with needle on one end and connector on other end. Hold a ruler in position, and slowly tighten vise til 1.125" is met.
On some aftermarket IACs, you screw in the needle to meet the 1.125". Then reposition the spring to maintain the position.
Clean throttle body with carb cleaner and toothbrush.
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Ron Dittmer - Driving A Mint 88GT, Automatic, Medium Red Metallic, Gray Interior, Black Lace Wheels, With Sunroof and Wing, in the Chicago area.