FixVault

General Pinpoint Test 11: Fuel Injector Inspection

PINPOINT TEST 11 - FUEL INJECTOR INSPECTION

PINPOINT TEST 11 FUEL INJECTOR INSPECTION
STEP INSPECTION ACTION
1 LISTEN FOR INJECTOR OPERATION
  • Warm up engine and run at idle (or cranking if engine will not start).
  • Listen for "clicking" sound from the injectors (use stethoscope if necessary).
  • Are all injectors "clicking"? 
Yes Go to step 3.
No Go to next step.
2 CHECK INJECTOR RESISTANCE
  • Disconnect suspect injector connectors.
  • Measure resistance of injectors.
  • Is resistance between 11-13 ohms for 2.3L, 11-18 ohms for 4.0L or 8.5-15.5 ohms for 3.0L? 
Yes Check injector driver circuits from PCM.
No Replace injector(s).
Go to next step.
3 CHECK INJECTORS FOR FUEL LEAKAGE
WARNING:
  • Before performing the following, operation, release the fuel pressure from the fuel system to reduce the possibility of injury or fire.

    See FUEL PRESSURE RELIEF .

Yes Fuel injectors are not leaking.
No Check for leaking O-rings and fuel rail damage. Repair or replace as necessary.