You've got everything whacked out, thinking that that screw your adjusting is for idle speed. It is not. It is the "minumum air bleed screw" and is used to maintain correct IAC (Idle Air Control) numbers.
Here's what you do. Assuming you have a scan tool that will read IAC.
First of all let's baseline everything. Turn the screw so that only 1/2 to 1 thread is showing through on the front side of the boss it's mounted in. Then adjust the idle TPS for .40
Now check IAC with engine warmed and idling in park. Does it read between 15-25?? If not it can be adjusted.
If it's lower than 10, turn the screw CCW 1/4 turn at a time to get the desired numbers above, you will notice a slight change in idle speed, but it will come back to normal. IMPORTANT, at this point also adjust the TPS back to .40 (It will have moved away from .40)
If however your IAC is higher than 30 and needs to be reduced a little, you can turn the screw CW in 1/4 turn incraments to get into the values stated earlier. IMPORTANT, at this point, adjust the TPS to get it back to .40 (adjusting the IAC moves it)
As you can see, adjusting IAC and TPS affect each other. It's a little tedeous, but when they are both adjusted properly, the rewards will be worth it.
Forget the IAC reset procedure. It does nothing more than get a whole lot of people in trouble and yields a whacked out IAC 9 times out of 10. Do the adjsutments above, get the numbers where they belong and you'll be MUCH happier.
