Maybe.
Let's demystify IAC and TPS.
When somebody says they're going to adjust IAC, what they really mean is that they're going to set minimum air, so that the IAC falls within a particular range of values.
Turning the minimum air screw in (i.e. clockwise) opens the throttle plate, allowing more air through the TB, lowering IAC and raising TPS. Conversely, backing the minimum air screw out (i.e. counterclockwise) closes the plate, raising IAC and lowering TPS.
That's all there is to it. Other than to say you need a scan tool that reads IAC and TPS.
The chip establishes idle RPM, unless you've screwed up and turned the minimum air screw in too far, and it "takes over".
"Mechanical" problems, such as vacuum leaks or the throttle plate not sealing in the bore, as can be the case with some aftermarket TBs, can also mess things up, causing artificially low values of IAC. Think about it. Leaks have the same effect as increasing minimum air.
Another "mechanical" problem to be on the lookout for is a weak or dirty IAC or dirty TB.
Make these adjustments when the car is fully warmed up. Some guys make their adjustments with the car in P, some in N, some in D, with the help of a buddy (don't get run over). Whatever.
Turn the key off to reset the IAC (the pintle will retract), as needed.
Check the values, once, twice, three times. Then drive the car a bit, and recheck your values.
Set WOT TPS with the car not running (good idea).
It's just that simple.
End of mystery...
