Rough Idle
- Check for intake air leaks.
- Check idle speed adjustment.
- Check Positive Crankcase Ventilation (PCV) system.
- Check Exhaust Gas Recirculation (EGR) system.
- Check Idle Air Control (IAC) Valve.
- Check fuel injector circuit.
- Check fuel delivery.
- Check fuel evaporative emission circuit.
- Check ignition timing and ignition circuit.
- Check Camshaft Position (CMP) sensor circuit.
- Check Mass Airflow (MAF) sensor circuit.
- Check front Heated Oxygen Sensor (HO2S) circuit.
- Check Throttle Position (TP) sensor adjustment and circuit.
- Check main power supply and ground circuits.
- Check engine mechanical condition.