High Idle problem

Reply Subscribe

Thread Tools

Search this Thread

Mar 25, 2008 | 05:47 PM

lectricman

Thread Starter

Mountain Pass

Joined: Feb 2004

Posts: 197

Likes: 0

From: In the swamps of Florida

High Idle problem

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.

Mar 27, 2008 | 05:26 PM

LxMan1

Moderator

Joined: Dec 2001

Posts: 22,436

Likes: 17

From: Louisville,Ky.

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?

Mar 27, 2008 | 05:52 PM