Fails Emission Test
- Check for clogged air filter.
- Check for engine not at normal operating temperature.
- Check for fuel leakage from injectors.
- Check for fuel pressure out of specification.
- Check for faulty coolant (water) temperature sensor.
- Check for faulty air temperature sensor (if equipped).
- Check for faulty ECM.
- Check for faulty EGR system (if equipped).
- Check for improper ignition timing.
- Check for lead contamination in catalytic converter.
- Check for malfunctioning ignition system.
- Check for misrouted vacuum hoses.
- Check for poor compression.
- Check for vacuum leaks.