Fuel Injector: Testing and Inspection

Fuel Rail Plug Bolt:

Comp. Loc:

FUEL INJECTOR BALANCE TEST

TOOLS REQUIRED
J34730-1 Fuel Pressure Gage
J39021 Fuel Injector Tester
J39200 Digital Multimeter
J41011 Fuel Pressure Gage Adapter

PROCEDURE
1. Relieve fuel pressure. Refer to Fuel Pressure Relief Procedure under Service and Repair. Service and Repair
2. Remove fuel plug bolt from fuel rail (refer to image).
3. Install a J41011 Fuel Pressure Gage Adapter to fuel rail (refer to image).
4. Install a J34730-1 Fuel Pressure Gage to J41011 Fuel Pressure Gage Adapter (refer to image).
5. Reconnect negative (-) battery cable. Tighten negative (-) battery cable-to-negative (-) battery terminal retainer to 15 Nm (11 lb. ft.).
6. Remove the fuel injector connectors from injectors No. 1 and No. 4.
7. Remove the two bolts from the throttle cover to access fuel injector connectors No. 2 and No. 3.
8. Remove cover.
9. Disconnect the fuel injector connectors.
10. Connect the J39021 Fuel Injector Tester to the vehicle battery.
11. Connect the J39021 injector test lead to fuel injector number one.
12. Set the amperage supply selector switch to the "0.5-2.5 AMP" "BALANCE TEST" position.
13. Cycle fuel pump "ON/OFF" (turn ignition switch "ON" and "OFF").
14. Record the stabilized fuel pressure (1st pressure reading).
15. Energize the fuel injector by pressing the "PUSH TO START TEST" button.
16. Record the fuel pressure gage reading once the needle has stopped (2nd pressure reading).
17. Repeat Steps 13 through 16 on the other three fuel injectors.
18. Subtract the "2nd pressure reading" from the "1st pressure reading" to obtain pressure drop values.
19. Add all four pressure drop values and divide them by four to get the average fuel pressure drop.

^ Any fuel injector that has more than a 10 kPa (1.5 psi) difference, either more or less from the average, is considered faulty. Any injectors which appear faulty should be retested. If retest fails, replace fuel injectors(s).

20. Relieve fuel system pressure. Refer to Fuel Pressure Relief Procedure under Service and Repair.
21. Disconnect J34730-1 and J41011 from fuel rail. Use shop towel to catch any remaining fuel that may leak.
22. Install fuel rail plug bolt. Tighten fuel rail plug bolt to 45-55 Nm (33-39.5 lb. ft.).
23. Reconnect all four fuel injector connectors.
24. Install throttle cover; secure with two bolts. Tighten two throttle cover bolts to 15 Nm (11 lb. ft.).
25. Connect negative (-) battery cable. Tighten negative (-) battery cable-to-negative (-) battery terminal retainer to 15 Nm (11 lb. ft.).
26. Turn ignition switch to "ON," and then back to "LOCK" to pressurize the fuel system. Check for any fuel leaks.