Engine will not idle down?

2002 FORD WINDSTAR

140,000 MILES • 8.1L • V8 • 2WD • AUTOMATIC

DON_JUAN

MEMBER
1 POST

I'm having a high idle issue and cannot get the idle down. It is not the adjustment screw. I have checked and checked and have no vacuum leaks. IAC is a Motorcraft CX-1766, a PWM style. Does the IAC close all the way when the engine is warm? WIth the IAC off (unbolted) and adjusting the duty cycle with the scanner, I do not see the pintle close all the way. Should I be able to see the pintle move when commanded by the PCM?

Feb 7, 2021 at 4:32 AM

SEVAG P

✓Experienced Mechanic
405 POSTS

hello.

is your engine v6 3.8L?because its not available v8 8.1L version, let me know the size of the engine.

many things can cause these issue, check the throttle cable if its routing correct and working properly, as you checked no external vacuum leak, its possible from the PCV system or idle air control , to narrow down our problem read the fault codes and send to us for proper diagnosis.

check our link below how to read fault codes.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Check our guide how fix high idle and how to service it.

https://www.2carpros.com/articles/engine-idles-too-high

https://www.2carpros.com/articles/idle-air-control-valve-service

Check the diagrams below throttle valve correct routing, idle air control remove and reinstall with test procedure.

let us know what happens with you, if you read fault codes send to us please.

thank you.

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Feb 7, 2021 at 7:12 PM