I have an 01 F150 with 5.4 engine. Yesterday when I got to work and parked the truck the idle went to 2200 rpm when I put it in park. The ride to work is about 20 miles, so the engine was warm. I shut the engine off and restarted and it was back to normal. This has happened once before (last summer). What would cause this?

Thanks.

 

Could be the IAC ( Idle Air Control ) or a vacum leak. Any codes?

 

Engine light's not on, so I assume no codes. Idles and runs well almost all the time. I've only had it do this twice, just figure something is getting ready to fail and hoping I can figure it out and catch it before I get stuck somewhere.

 

Sticky IAC valve.

 

Thanks. Is that something I can clean/lube or is it a replacement item?

 

I've heard of people removing and cleaning them. A new Motorcraft is 70 bucks at rockauto.com, aftermarket is around $50.

 

Not sure about your truck, but i had a 95 z71 that had a problem with it's throttle position sensor