P0505

DTC P0505: Malfunction in Idle Control System

NOTE: If DTC P1519 is stored at the same time as DTC P0505, troubleshooting DTC P1519 first, then recheck for DTC P0505.

1. Start the engine. Hold the engine at 3,000 rpm with no load (in neutral) until the radiator fan comes on then let it idle.
2. Check the engine speed at idle with no-load conditions: headlights, blower fan, rear defogger, radiator fan, and air conditioner are not operating.

Is it 900 ± 50 rpm?

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

NO - If the idle speed is less than 850 rpm, go to step 3; if it's 950 rpm or higher, go to step 4.

3. Disconnect the 3P connector from the IAC valve.

Does the engine speed increase or fluctuate?

YES - Check the idle speed. If it's impossible to set, clean the ports in the throttle body.

NO - Replace the IAC valve.

4. Turn the ignition switch OFF.
5. Remove the intake air duct from the throttle body.
6. Start the engine and let it idle.




7. Block both the round by-pass port (A) and the rectangular IAC port (B) in the throttle body with your fingers.

Does the engine stall?

YES - Replace the IAC valve.

NO - Check for vacuum leaks, test the throttle body, and repair as necessary.