that would be the IAC reset function of the ECM. it pulses the IAC at either 80 or 160 Hz (or at least it does on later systems) to fully extend/retract/whatever.

obviously, it's not a single...

pulse it at an 80Hz frequency with 12 volts and it will move as it is supposed to. i imagine the average tech (at least back then) wouldn't know what to think of a little IAC motor that moves an...

yeah, the same voltage the ECM gets from the ignition circuit is what gets fed to the IAC.

IAC is definitely 12 volt, if you have a scope, you can confirm this, however GM schematics imply it as well as Ludis's document all imply that the IAC is driven directly off of system voltage.