Minimum Air Idle Adjustment

[XfireZ51]

There's been several threads whee this topic comes up. I had documented it as part of another thread but thought I would set it up for its own to make it easier to find. Would make a good sticky.

OK. Here goes:

As for setting the IAC count for Minimum Air, the procedure I follow is:
(Do this procedure once you have warmed motor to C/L operating temps. otherwise it may very well not idle. Also, you will have converted your throttle stop stud to a hex bolt I think a 7mm hex head.)

1. Jumper the ALDL as you would for reading codes.
2. Turn ignition to ON, not start.
3. Leaving ignition ON, remove the IAC harness connector. This fully extends the IAC pintle and closes off the IAC port.
4. Shut ignition OFF and remove the ALDL jumper.
5. Start the motor and get it to idle. May need to use a bit of throttle at first.
6. Check idle rpm. Turn the throttle stop screw until the motor is idling at an rpm just below what your target idle rpm. I want my idle at 875-900, so I set Min Air throttle at 800-825rpm. You may need to adjust TPS Voltage so that ECM stays within idle TPS Voltage range.
7.Tighten everything up and shutoff motor.
8. Plug in IAC. I also undo the negative BATT cable to drain the ECM memory.
9. Reconnect BATT turn ignition ON, and check TPS V. Adjust to .53-.57v if necessary.
10. Start motor and quickly raise to ~2000rpm for a brief period. This resets the IAC.
11. Shutoff motor, then restart. Allow motor to idle down and check your IAC counts and your TPS Volt which may need to be adjusted one more time.