Another Idle Question-'86 302

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Nov 2, 2002 | 06:58 PM

fishingboy

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Another Idle Question-'86 302

This is on a 1986 F150 w/302. With a warm engine, when I put the truck in park or neutral, or re-start a warm engine, the idle drops WAY LOW for 2-3 seconds, then comes back up. It idles fine in drive. I have cleaned the AIC valve. This is EFI. I also sprayed carb cleaner around the vacuum lines with no change. Any and all ideas will be explored, thanks. PS-the idle speed in neutral seems quite lower than it does in drive.

Nov 3, 2002 | 05:04 PM

steve83

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From: Memphis, TN

Another Idle Question-'86 302

Check the IAC valve for carbon buildup & the servomotor for correct resistance. Also check the TPS and set it to 1.0V at idle. You can find all this in a Haynes manual ($12).

Nov 3, 2002 | 11:10 PM

Franklin2

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Another Idle Question-'86 302

Also check the idle speed adjustment screw. To do this, unplug the idle air control solenoid wiring plug with the truck at idle. The truck should struggle a little, then die. If it cuts off right away, the idle adjustment is backed off too much. If the truck keeps running, the idle screw is screwed in too much.

Nov 4, 2002 | 05:54 AM

fishingboy

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Another Idle Question-'86 302

Would u happen to know how to hook up a dwell/tach to this truck? It's not like my other vehicles that had a standard coil available to hook up to.......