How to Change the Idle Air Control on a 2003 Ford Taurus

by Steve LaNore

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.

Use engine cleaner before removing old IAC.

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.

Remove Old IAC


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 New IAC


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.


  • check Use engine cleaner before repairing to reduce the chance of dirt falling inside.
  • check Place a rag or mechanic’s mat over the fender to protect the paint.
  • check Use a small rag to plug the hole, and don’t push it in more than 1/2 in.
  • check Keep the old IAC or its packaging until you’re sure this repair corrects the problem. The parts store might accept a return.
  • check The new IAC will begin in a default mode due to the loss of battery power. The engine computer will quickly relearn the control pattern for best performance. Drive around town making frequent stops; this will speed the process.


  • close Wait at least one hour after driving to allow engine to cool.
  • close Don’t lay tools on the battery or on the top of the engine.
  • close Do not attempt this repair with the battery connected; you risk being shocked, and damaging engine components.
  • close Do not use a high-pressure sprayer when cleaning around the IAC.
  • close Do not insert objects into the throttle opening or you might damage the throttle plate.
  • close Gently clean the mating surface so you do not gouge the metal.

Items you will need

About the Author

Steve LaNore has written and produced broadcast reports/specials and printed literature since 1985 and been a Web writer since 2000. His science blogs/reports can be seen on the Web site of KXII-TV. LaNore is a five-time award-winning meteorologist and member of the American Meterological Society as well as a Certified Broadcast Meteorologist sealholder. He holds a Bachelor of Science in meteorology from Texas A&M University.

More Articles

Photo Credits

  • photo_camera électronique image by razorconcept from