2000 F250 5.4 SD low idle speed

rvrunner · #1 (**permalink**) 12-09-2007, 03:28 PM

Idle speed is usually around 750 but currently is closer to 450. When starting, acceleration is required to keep the engine running until it warms up a bit. Then it idles at 450. Following acceleration, it will die if assistance via gas pedal is not given. This problem would occur occasionally in the past, once every 6 months or so but would return to normal (750 rpm) idle after a few minutes. Currently idle is remaining at 450 rpm. I thought it might be the air idle control. Any suggestions? And does anyone have pictures of the AIC for this model.

Joe Finn · #2 (**permalink**) 12-09-2007, 05:53 PM

Sounds like the IAC to me. I don't have a picture, but it should be right on top of the throttle body. If you pick up a new one, you'll have no trouble finding where it goes.

rvrunner · #3 (**permalink**) 12-09-2007, 06:03 PM

Thank you for your reply. I spent a bit more time on this site and found a couple of pictures of a IAC. However these appeared to be mounted along the side of the throttle assembly. If I am correct, mine is located on the back of throttle assembly with the retaining bolts facing the firewall. I'll try to clean it first since it was an intermitten problem prior to becoming the constant problem that it is.
Anyone with other thoughts or pictures feel free to post as well.

Thanks
Jim

Ultramagdan · #4 (**permalink**) 12-09-2007, 09:12 PM

Just two small bolts hold it on. Be sure and place a rag underneath them so you don't drop them when you remove them.

rvrunner · #5 (**permalink**) 12-10-2007, 06:28 PM

Replaced the AIC this afternoon. I didn't drive it much today, but it starts and idles just fine.

Thanks for the help.
Jim