How to Change an IAC Valve for a 2000 Ford F-150

Iskandar Blogger 4:35 PM

The 1988 model year marked the first time in the F-150s production life that all of its engines came with electronic fuel injection. With these fuel-injected engines came additional electronic controls. Monitoring and adjusting the idle speed is the job of the idle air control valve. The IAC valve performs its task by adjusting the amount of air that bypasses the throttle plate and enters the intake manifold at idle. The 2000 F-150 was far more advanced than its 1988 counterpart, but it used the same IAC-valve system to adjust the trucks idle. Replacing the 2000 F-150s IAC valve is a straightforward process on all three of the pickups available engines.

Instructions

    1

    Remove the three screws securing the plastic throttle body cover on the 4.6-liter and 5.4-liter engine with a ratchet and socket. Pull the throttle body cover up and off the engine.

    2

    Find the IAC valve mounted on the F-150s intake manifold. The IAC valve is on the right rear of the engine on the 4.2-liter engine. Ford positioned the IAC valve on the front left of the engine on the 4.6- and 5.4-liter engines.

    3

    Press and hold the unlocking button on the IAC valve wiring harness, and unplug the harness from the receptacle on the IAC valve.

    4

    Pull the throttle bypass hose from the IAC valve on 4.6- and 5.4-liter engines. Remove the IAC-valve-retaining bolts with a ratchet and socket. Pull the old IAC valve gasket off the intake manifold and clean the mating surface on the manifold with a plastic scraper. Be careful not to get any debris in the intake manifold.

    5

    Set a new IAC valve gasket on the IAC valve mating surface on the intake manifold, lining up the bolt holes on the gasket with those on the intake manifold. Set the new IAC valve on the intake manifold and hand-thread its retaining bolts.

    6

    Tighten the IAC-valve-retaining bolts from 8 to 9 foot-pounds with a torque wrench and socket. On Lightning model F-150s, tighten the IAC valve bolts an additional quarter-turn with a ratchet and socket.

    7

    Plug the wiring harness back into the IAC valves receptacle. Plug the throttle bypass hose onto the IAC valve on 4.6- and 5.4-liter engines.

    8

    Set the throttle body cover back in place on top of the 4.6-liter and 5.4-liter engines, and hand-thread its retaining bolts. Tight the three throttle-body-cover-retaining bolts to 5 foot-pounds with a torque wrench and socket.