Idle Air Control Valve (PRIZM)
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 DTC P0505. For test procedure with DTC set, see appropriate SELF-DIAGNOSTICS article.