Rough Idle
- Check switch condition signal. See CODE 51 in appropriate TESTS W/CODES article.
- Check idle speed control valve circuit.
- Check airflow meter circuit. See CODE 31 and CODE 32 (ES300) in appropriate TESTS W/CODES article.
- Check injector circuit.
- Check EGR system.
- Check ignition circuit. See CODE 14 in appropriate TESTS W/CODES article.
- Ensure engine compression is within specification.
- Check fuel system circuit.
- Ensure ignition coil resistance values are within specification.
- Check distributor.
- Check spark plugs.
- Check ECM memory power circuit.
- Check cold start injector system (ES300 & SC400).