Idle Air Control (IAC) Valve

Idle Air Control (IAC) valve is located on bottom of throttle body. IAC valve opens and closes air by-pass passage according to signal from PCM. When open, air is supplied to intake manifold, which increases engine RPM for different engine loads. A malfunction in IAC valve circuit can set Diagnostic Trouble Code (DTC) P0505. For testing procedures, see TESTS W/CODES article.