Rough Idle
- Check engine mechanical condition.
- Check fuel delivery.
- Check fuel pump circuit.
- Check fuel pressure regulator.
- Check fuel injector circuit.
- Check fuel evaporative emission circuit.
- Check Positive Crankcase Ventilation (PCV) system.
- Check Idle Air Control (IACV)-Air Regulator.
- Check idle speed adjustment.
- Check Idle Air Control Valve-Auxiliary Air Control (IACV-AAC) valve circuit.
- Check Idle Air Control-Fast Idle Control Device (IAC-FICD) circuit.
- Check ignition timing and ignition circuit.
- Check Exhaust Gas Recirculation (EGR) system.
- Check main power supply and ground circuits.
- Check radiator (cooling fan) circuit.
- Check A/C circuit.
- Check Camshaft Position (CP) sensor circuit.
- Check Mass Airflow (MAF) sensor circuit.
- Check front Oxygen Sensor (O2S) circuit.
- Check Throttle Position (TP) sensor adjustment and circuit.
- Check Engine Coolant Temperature (ECT) sensor circuit.
- Check start signal circuit.
- Check Knock Sensor (KS) circuit.
- Check Park/Neutral position (inhibitor) switch circuit.
- Check power steering oil pressure switch circuit.
- Check PCM inputs/outputs and PCM.