Can IAC be set this way?
Thread Starter
Drifting
Joined: Jul 2002
Posts: 1,488
Likes: 4
From: Frostburg MD
Can IAC be set this way?
I've read to set the IAC you should jumper some pins, unplug the IAC connector, and to set the throttle stop screw until you reach a certain idle. Instead of that, could I just wait for the car to warm up, then set the throttle stop screw until the IAC counts read 30 on my scan tool? I know I'd have to adjust the TPS afterwards as well. Will this way work? It would seem to be easier if it did. I have an '89.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Can IAC be set this way? (shotchkiss)
I've not tried that method but let us know how it works out.
But you would still need to use the old method so that you could set the TPS base value. Of course you could then read the TPS value at normal idle and use that value as a future setpoint.
But you would still need to use the old method so that you could set the TPS base value. Of course you could then read the TPS value at normal idle and use that value as a future setpoint.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Re: Can IAC be set this way? (shotchkiss)
I don't think so - the ECM will get a signal that the engine is accelerating if you increase the throttle with the screw and ignore the IAC and once that happens, idle will probably be about a 1000 rpms or so. Since you have a scan tool, turn on the ignition and ground the diagnostic connector to fully extend the IAC. Leave the ignition on and disconnect the IAC and the distributer timing connector. Start the engine and use the RPM readout on the scanner to set base idle to 425-450. Turn off the engine. Reset the TPS to .054. Reconnect the distributor. Depress the accelerator slightly for 5 seconds. Start the car and let it run for 10 seconds. Idle should be no more 50 RPM above whatever the ECM is targeting for RPM.
