Replacement IAC valve for 1984-85 Regal Grand National and T-Type models.The function of the idle air control valve is to regulate the air around the throttle valve by extending or retracting a tapered pintle valve in the air passage. Its main function is at idle. This is the part that helps control an even idle.If you are experiencing a cold start idle that goes up and down chances are this idle air control valve is at fault due to dirt or foreign material around the tapered pintle.The idle air control valve is located directly under the throttle body and can be recognized by the 4-wire plug that goes to it.
