Tahoe 2WD V8-4.8L VIN V (2004)
Fuel Injector: Testing and Inspection
Fuel Injector Coil Test
FUEL INJECTOR COIL TEST
CIRCUIT DESCRIPTION
The control module enables the appropriate fuel injector pulse for each cylinder. Ignition voltage is supplied directly to the fuel injectors. The control
module controls each fuel injector by grounding the control circuit via a solid state device called a driver. A fuel injector coil winding resistance that is
too high or too low will affect engine driveability. A fuel injector control circuit DTC may not set, but a misfire may be apparent. The fuel injector coil
windings are affected by temperature. The resistance of the fuel injector coil windings will increase as the temperature of the fuel injector increases.
DIAGNOSTIC AIDS
-
The use of Dielectric compound GM P/N 12377900 (Canadian P/N 10953529) in the fuel injector electrical connector may eliminate a corrosion
condition.
-
Monitoring the misfire current counters, or misfire graph, may help isolate the fuel injector that is causing the condition.
-
Operating the vehicle over a wide temperature range may help isolate the fuel injector that is causing the condition.
-
Perform the fuel injector coil test within the conditions of the customers concern. A fuel injector condition may only be apparent at a certain
temperature, or under certain conditions.
-
If the fuel injector coil test does not isolate the condition perform the fuel injector balance test. Refer to Fuel Injector Balance Test with Special
Tool or Fuel Injector Balance Test with Tech 2. See: Computers and Control Systems/Testing and Inspection/Component Tests and General
Diagnostics See: Computers and Control Systems/Testing and Inspection/Component Tests and General Diagnostics
TEST
Steps 1-7
