Owners of vehicles built from 2001 onward should avoid cleaning the throttle body interior since this may lead to engine performance problems due to its sludge-resistant material. Manufacturers set the minimum idle speed during production and owners cannot alter this value because any idle problems involving stalling or variations should check the Idle Air Control Valve for damage. The IAC valve enables airflow bypassing around the throttle valve through voltage pulses received from the PCM to control idle speed. The IAC valve connector should display a normal voltage signal within 10.5 to 12.5 volts range while the engine ignition is active. A proper voltage reading should lead to resistance testing of the IAC valve terminals which should measure between 6.0 to 13.0 ohms. The resistance test should be conducted by measuring either terminal to the IAC body which should measure above 10,000 ohms. The pintle along with valve housing requires cleaning from carbon residue. The IAC valve replacement begins when the connector is unplugged followed by removing the snow shield then detaching the valve assembly before inspecting the O-ring for damage. Start by cleaning the sealing surfaces followed by engine oil lubrication of the new O-ring then place the IAC valve assembly and finally secure the screws before connecting the electrical connector.
