Chart 12-Backfire (Intake Or Exhaust)

DIAGNOSTIC CHART 12-BACKFIRE (INTAKE OR EXHAUST)

System & Component(s)	Reference
IGNITION Scope Engine For: Spark Plugs, Wires, Coil, etc. Crossed Wires, Ignition Timing	See BASIC TESTING article.
VACUUM DISTRIBUTION Vacuum Hoses, Connections	Perform a visual and audible inspection.
EEC EEC-IV Quick Test	See TESTS W/CODES article.
THERMACTOR Thermactor System Components	See I - SYS/COMP TESTS article.
BASE ENGINE Intake Manifold and Gaskets Compression Checks Camshaft Valves	Check Engine Mechanical Condition.
EXHAUST Component (Restricted)	Inspect exhaust system.
FUEL/THROTTLE BODY Fuel Filter Fuel Pump Water/Dirt/Rust Contamina- tion in Fuel Fuel Lines Fuel Pressure Regulator Injectors Fuel Sender Filter Octane	Perform a visual inspection. See FUEL SYSTEMS in I - SYS/COMP TESTS article.