Truck won't idle
 

I have a 2001 F 150 surercrew 5.4L that on random startup don't won't to idle (arround 400 rpm). It doesn't do it all the time, just at random. I have replaced the fuel pump, fuel filter but that didn't fix the problem.If iI give it a little gas when its idling low it will eventuallly pick up the correct idle (arround 750). I have cleaned all the componants above the intake manifold, but no fix yet. I read on this forum that some models have a fuel control module, I looked and didn't find one on mine. Can anyone help? Thanks in advance!

No fuel control module (FPDM) on a 01, it's a full return system with a pressure regulator on the rail. You can borrow/rent a fuel pressure gauge to check that. Why did you replace the fuel pump before checking that?

Clean or replace the IAC (idle air control).

I checked the pressure and it was 34 psi and the tech said it should be above 40 to work proper. Is the IAC a electronic piece?

It should idle fine at 28 or higher. The pressure should go up when you remove the vacuum hose from the regulator.

The IAC is electro-mechanical.

https://info.rockauto.com/getimage/g...aft/cx1867.jpg

Above 40 ? That's incorrect. Like glc said, 28 psi is a good pump. 34 psi is average. Above 40 would be without regulator.

Thanks for the info glc. I'll check it out!

Thanks jbrew for the backup!

No problem. He's right about the IAC as well. You can either clean it up inside w/DeepCreep while working the mechanicals w/compressed air to assist. OR, just purchase a new one.

That's why it won't idle.

Thank you glc and jbrew!!! Replaced the IAC and truck idles fine! Hope I can be of service to you both some day!

Jbrew rocks! He's helped me several times, he is a HUGE asset to this board.

Yeah, these guys (and many others) are a huge asset to this board. Invariably the answers you need are here. Great site, great posters.

This might be the proper time to put in for a raise. (?)

:beers:

Great info! I'm having the same random idle problem. Where is that part located? Other wise truck runs fine.