does anyone know the readings on the iac connector

 

Readings? As in square wave pulse rate? Amplituide? Resistance at the IAC itself?

 

it appears when i check it at the plug im getting about 12.5 on two prongs and about .50 on the other two. this is the four prong square type plug in.

 

The Idle Air Control stepper motor uses two phased coils to position the pintle. The ECM will pulse square wave signals to the IAC to drive it inward or outward at various pulse widths to control the rate of movement. Readings you might get with a plain voltmeter are relatively meaningless. You'd have to monitor both sets of outputs on a dual trace oscilloscope to determine if the ECM output is correct or not.

Let's step back a pace or two. You have lots of posts with questions about various, seemingly unrelated components or devices. Are you having issues with each of them, or are you simply curious about their operation? Or is this a pop quiz to see if we can explain the systems?

There are many good references in print that describe the purpose and operation of each engine control input or output device on these vehicles. The factory service manual is a good starting point, and is fairly comprehensive.

If you are having a specific set of operational issues with your vehicles, rather than taking this "back door" approach, a thorough description of the problem(s) might yield resutls much faster.