Fuel Injector: Testing and Inspection

W/Engine Running

1. Start engine and allow to idle, then disconnect injector electrical connectors one at a time. Idle speed should drop equally for each cylinder.
2. Check clicking sound of each injector using a suitable stethoscope with engine idling. Injector should make a typical clicking sound.
3. If steps 1 and 2 are not satisfactory, check wiring between ECU and injector. If wiring is satisfactory, replace defective fuel injector.

Engine Cannot Be Started

1. Remove injector electrical connector and measure resistance between injector terminals. Resistance should be 1.5-2.5 ohms.
2. If resistance is not as specified, replace injector. If resistance is as specified, proceed as follows:
a. Check for short circuit, wire breakage or poor connection in wiring between resistor and injector, or between resistor and main relay.
b. Check for proper operation of resistor.
c. Check for short circuit, wire breakage or poor connection in wiring between resistor and control unit.