Engine Controls - Trouble Shooting - No Codes: Symptoms: Backfire: Ascender
- Perform On-Board Diagnostic II System Check.
- Perform Electronic Throttle Control (ETC) System Check.
- Inspect the ignition system.
- Inspect the engine for compression, improper valve timing, manifold gaskets, and sticking or leaking valves. Inspect the intake manifold and exhaust system for fresh air entering the exhaust upstream of the catalytic converter or restrictions.
- Inspect the fuel system. See FUEL SYSTEM DIAGNOSIS under FUEL SYSTEMS in BASIC DIAGNOSTIC PROCEDURES article.
- Perform the Fuel Injector Balance Test. See FUEL INJECTOR BALANCE TEST under FUEL SYSTEMS in SYSTEM & COMPONENT TESTING article.