Poor DRIVEABILITY: Backfire
- Check for vacuum leaks.
- Check EGR system. See CODE 71 in TESTS W/CODES article in the ENGINE PERFORMANCE Section.
- Check water temperature sensor circuit. See CODE 22 in TESTS W/CODES article in the ENGINE PERFORMANCE Section.
- Check intake air temperature sensor circuit. See CODE 24 in TESTS W/CODES article in the ENGINE PERFORMANCE Section.
- Check throttle position sensor circuit. See CODES 41 & 47 in TESTS W/CODES article in the ENGINE PERFORMANCE Section.
- Check airflow meter circuit. See CODE 31 in TESTS W/CODES article in the ENGINE PERFORMANCE Section.
- Check fuel system circuit. See FUEL SYSTEM CIRCUIT chart in I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.
- Check injector circuit. See INJECTOR CIRCUIT chart in I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.
- Check valve timing and timing belt.
- Check ECU.