DTC P0506: Idle Control, Rpm Low: Condition

DTC is set when brake pedal is depressed, steering wheel is straight and actual engine speed is 100 RPM lower than expected for 14 seconds. PCM will not set DTC when atmospheric pressure is less than 21.3 in. Hg or intake air temperature is less than 14°F. Possible causes are:

• Idle Air Control (IAC) valve malfunction.
• Air filter or intake is clogged.
• A/C relay control circuit malfunction.
• Generator control circuit malfunction.
• Purge control solenoid valve malfunction.
• Low engine compression (blowby).
• PCM malfunction.