The idle air control, or IAC, is an electric valve which regulates the flow of air into the Ford Taurus' engine during idle. The amount of air the engine needs changes as speeds increase, so the IAC is inactive during highway driving.
A defective IAC can cause the Taurus to stall when idling, and run rough when the vehicle is driven at low speeds. The IAC is in plain view on the 2003 Ford Taurus, and it’s quite easy to replace.
Park the vehicle on a level surface and apply the emergency brake.
Open the hood and disconnect the negative battery cable with a socket wrench.
Lean over from the driver’s side to locate the IAC. It is a silver-colored cylinder bolted to the air duct near the large, fluted rubber hose.
Apply engine cleaner around the IAC valve. Allow the cleaner to soak for a few minutes, and then wash it off with moderate hose pressure. Gently dry the area with a soft cloth.
Unhook the electrical connector on the idle air control with a separator tool or small screwdriver.
Unscrew the two bolts with a socket wrench. Set aside the old IAC.
Place a lint-free rag just inside the opening and wipe away any grime around the mating surface with a second rag. Carefully remove the rags.
Install the new gasket and IAC. Secure the bolts to 89 in.-lbs., or about 7 ft.-lbs, with a torque wrench.
Wipe away any dirt or moisture from the wires. Reattach the electrical connector. Make sure it snaps into place.
Reconnect the battery cable. Close the hood, start the engine and drive the car for at least 15 minutes.
