DTC P0506: Idle Control System Rpm Lower Than Expected Or DTC P0507: Idle Control System Rpm Higher Than Expected
NOTE:
If any trouble codes are set besides DTC P0506 or P0507, diagnose them first.
- Ensure electrical wiring, emission control hoses and air cleaner are all okay. Turn ignition on. Turn off all accessories. Ensure ignition timing is set properly. Run engine to normal operating temperatures.
- Locate test connector beside PCM. Connect fused jumper wire between test connector terminals "B" and "D". See Fig 1 . Connect duty meter to test connector terminals "D" and "F". Idle speed should be 700-800 RPM with IAC duty reading of 8-25% (10% higher at elevation of 6550 ft. or greater). If engine RPM is not within specification, go to next step. If engine RPM is within specification, check for an intermittent problem. See TESTS W/O CODES article.
- Perform testing procedure in DTC P0505, steps 1) and 2). Repair as needed. If IAC valve is okay, recheck IAC duty percent in step 2). If percentage is not within specification, check for vacuum leaks in emission control hoses and intake system. Also check for blockage in intake system. If percentage is within specification, replace PCM. Retest system.