P0506: Idle Air Control System Rpm Lower Than Expected (All Others)

WARNING: This page does not describe the selected car, but rather 30 other vehicles, including the 2004 Mercury Sable, 2004 Mercury Mountaineer, 2004 Mercury Monterey, 2004 Mercury Marauder, and 2004 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.

P0506 - IDLE AIR CONTROL SYSTEM RPM LOWER THAN EXPECTED (ALL OTHERS)

Description:	This DTC is set when the PCM detects an engine idle speed that is less than the desired RPM.
Possible Causes:	IAC circuit open. Air inlet is plugged. Damaged or incorrect IAC valve. IAC valve stuck closed. VPWR to IAC solenoid open. IAC circuit shorted to PWR. Damaged PCM.
Diagnostic Aids:	Disconnect the IAC valve and look for no change in engine RPM as an indication of a stuck or damaged valve.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All others	GO to PINPOINT TEST KE: IDLE AIR CONTROL (IAC) VALVE Step 2.	GO to PINPOINT TEST KE: IDLE AIR CONTROL (IAC) VALVE Step 2.	GO to PINPOINT TEST KE: IDLE AIR CONTROL (IAC) VALVE Step 2.