Hello all, I recently bought an '86 F-150 with a FI 302 and can't seem to correct a consistant high idle. I performed a self test to pull codes and everything passed on the KOEO and CM tests. On the engine running self test, I got the following codes:

44: Thermactor air injection system inoperative (right side)
13: Cannot control RPM during ER self test low RPM check

Would either of these affect the idle speed? I'm trying to narrow down the possibilities before I start throwing parts at it. I have already done the basics (tune up, fuel filter, o2 sensor, etc.)

Thanks for everyone's help.

 

Code 13 is caused by the high idle.
Either someone has turned the idle screw too far in or the IAC is stuck open.
Verify that the throttle blades are closed. If they are, then I would suspect either a vacuum leak or the IAC (Idle Air Control) valve is not working properly. Also, a TPS sensor set too high can cause a fast idle.
Any idea what rpm it is actually idling at?

 

About 1250 in park, 900 in gear. I checked the resistance across the terminals on the IAC and got a low reading, so I'm thinking its not working correctly.