P0506

DTC P0506: Idle Control System RPM Lower Than Expected (2004-2005 models)

NOTE: If DTC P0511 is stored at the same time as DTC P0506, troubleshoot DTC P0511 first, then recheck for DTC P0506.

1. Start the engine. Hold the engine at 3,000 rpm without load (in neutral) until the radiator fan comes on, then let it idle.
2. Check the engine speed at idle without load conditions: headlights, blower fan, rear window defogger, radiator fan, and air conditioner off.

Is the engine running at 750 ± 150 rpm?

YES - Intermittent failure, system is OK at this time.

NO - Go to step 3.

3. Turn the ignition switch OFF.
4. Disconnect the IAC valve 3P connector.
5. Start the engine, and let it idle.
6. Check the engine speed at idle without load conditions; headlights, blower fan, rear window defogger, and air conditioner off.

Does the engine speed increase or fluctuate?

YES - Check the idle speed with a different load condition (electrical, A/C, gear position, P/S, etc.). If it's out of specification, replace the IAC valve.

NO - Replace the IAC valve.