Engine Controls - Tests W/O Codes: Backfire: Exhaust
- Check air filter for restriction.
- Remove vacuum hose from fuel pressure regulator. Apply vacuum and pressure and monitor symptom change.
- Enter self-diagnostic Mode II and monitor fuel metering system operation.
- For Idle Switch: Enter self-diagnostic Mode IV and perform appropriate switch tests.
- For Ignition Signal: Enter self-diagnostic Mode V and monitor real-time diagnostic setting of fault codes. Perform appropriate code chart in TESTS W/CODES article.
- Check air injection valve. See AIR INJECTION under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM/COMP TESTS article.
- Check air injection valve solenoid.