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Fuel Injector Operation Inspection

FUEL INJECTOR OPERATION INSPECTION

STEP INSPECTION RESULTS ACTION
1 While cranking the engine, inspect for fuel injector operation sound at each cylinder using a soundscope.
Is operation sound heard?
Yes Fuel injector operation is normal.
No All cylinders not heard: 
Go to the next step.
Some cylinders not heard: 
Go to Step 3.
2 Perform main relay operation inspection.
Is main relay operation normal?
Yes Inspect the following:
  • Fuel injector power system related wiring harness and connectors
  • PCM connectors
  • Fuel injector GND and related wiring harness and connectors
No Repair or replace malfunctioning parts.
3 Switch fuel injector connector of not operating fuel injector with operating fuel injector.
Is operation sound heard?
Yes Go to the next step.
No Replace the fuel injector.
4 Are wiring harness and connectors of not operation fuel injector normal? (Open or short) Yes Inspect PCM terminal voltage of fuel injector signal.
No Repair or replace malfunctioning parts.