Fuel Injector Circuit Tests: IMPREZA
- Check Fuel Injector Operation
- Verify injector operation using a stethoscope or screwdriver to hear operating sounds while engine is cranked. If operating sounds are not heard, go to next step. If operating sounds are heard, verify fuel pressure. See FUEL PRESSURE
under FUEL SYSTEM.
- Check Fuel Injector Power Circuit
- Turn ignition off and disconnect each fuel injector connector. Turn ignition on. Measure voltage between each injector connector terminal No. 2 (Yellow wire) and ground. If at least 10 volts are present, go to next step. If less than 9 volts are present, repair harness or connectors as necessary.
- Check Fuel Injectors
- Measure resistance between each fuel injector terminals No. 1 and 2. Resistance between each terminal should be 11-12 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace fuel injector(s). See Fig 1
.
- Check Resistance Between ECU Connector & Each Injector
- Disconnect ECU 22-pin connector. Verify less than 10 ohms resistance between ECU connector terminals No. 1 (Light Green/Red wire), No. 2 (Brown wire), No. 12 (Blue/Red wire), No. 13 (Blue/White wire) and fuel injector terminal No. 1 of each fuel injector connector. If resistance is greater than 10 ohms, repair harness or connectors as necessary. If resistance is less than 10 ohms, inspect ECU connector terminal and repair as necessary. If ECU connector is okay, replace ECU.
Courtesy of SUBARU OF AMERICA, INC.