Set IAC w/o scanmaster

Lone_Domino

Member
Joined
Apr 19, 2004
Does anyone know how I can properly set the IAC w/o a scanmaster?

My 84 motor wants to sputter and die at idle ocassionally. I turned it up 1/2 turn and then adjusted the TPS back to .42v and it helped but it still does it ocassionally and idles about 600 in gear. With the A/C on it is fine because the computer turns the idle speed up. I can just turn it up more but would like to be more precise than that.

Thanks!
Mitch
 
Have you ruled out other problems?

This may go against everyone on here, but I like to set mine differently. I let the car fully warm up, make the IAC fully close, unplug IAC, and at hot idle in park, I set the idle speed with the adjustment on the TB. This seems to cure any and all sputtering and dying problems. Of course the IAC is plugged back in.

This way, the IAC can raise idle for AC, cold start, in gear, etc, but the minimum hot idle air is mechanically set.
 
Sounds like a good idea to me. Thanks, I will try it tomorrow and see if we can't get this gremlin fixed and move on to better things like boost/knock/oil pressure/water temp guages.
 
Iac

Try this procedure.
Pretty much what cool 84 said.
I got this from the Turbo Regal Wed Site
1. Ground ALDL diagnostic lead (short the top two rightmost pins in the ALDL connector).
2. Turn on the ignition (but don't start the car).
3. Wait 30 seconds.
4. Leave ignition on and disconnect the IAC connector.
5. Remove the grounding from the ALDL connector.
6. Start the car. The car will probably run rough and may stall. Just restart and try again.
7. Adjust the throttle stop screw to set the idle to 500 RPM +/- 50 RPM.
8. Turn the car off and reconnect the IAC connector.
9. Turn ignition on and adjust TPS to proper settings. (.42-.44 at idle is typical)
10. Repeat procedure until the 500 RPM +/- 50 RPM in step 7 can be maintained while TPS is at proper idle setting.
 
Try this procedure.
Pretty much what cool 84 said.
I got this from the Turbo Regal Wed Site
1. Ground ALDL diagnostic lead (short the top two rightmost pins in the ALDL connector).
2. Turn on the ignition (but don't start the car).
3. Wait 30 seconds.
4. Leave ignition on and disconnect the IAC connector.
5. Remove the grounding from the ALDL connector.
6. Start the car. The car will probably run rough and may stall. Just restart and try again.
7. Adjust the throttle stop screw to set the idle to 500 RPM +/- 50 RPM.
8. Turn the car off and reconnect the IAC connector.
9. Turn ignition on and adjust TPS to proper settings. (.42-.44 at idle is typical)
10. Repeat procedure until the 500 RPM +/- 50 RPM in step 7 can be maintained while TPS is at proper idle setting.


That's pretty much it, except in much better detail. The only thing I change is setting the idle at ~7-800rpm so IAC counts are near 0 with it idling in park.
 
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