Engine Controls - Tests W/O Codes - Except Diesel: Symptoms: Backfire

Download the full database via torrent (~1.1 TB) | Download Brad's custom LEMON patches

Check the following:

Check secondary ignition system.
Check PCM power and ground circuits.
Check fuel delivery.
Check fuel pressure.
Check Manifold Absolute Pressure (MAP) calibration.
Check minimum idle airflow.
Check oxygen sensor switching.
Check EGR system.