Idle Speed Fluctuates (MIL Works OK, No DTCs Set)

Idle speed fluctuates (MIL works OK, no DTCs set)

Diagnostic Procedure:

1. Do the ECM idle learn procedure. ECM Idle Learn Procedure

2. Check the idle speed. Testing and Inspection

3. Adjust the throttle cable. Adjustments

4. Do the carbon accumulation check. Testing and Inspection

5. Troubleshoot the A/C signal circuit. A/C Signal Circuit Troubleshooting

Also check for:

- Incorrect valve timing or clearance adjustment
- Intake air leaks