Fuel System Injector Balance Test

FUEL INJECTOR BALANCE TEST

J34730-1A Fuel Pressure Gage
J39802 Fuel Pressure Gage Adapter
J34730-3A Fuel Injector Tester
J34730-355 Fuel Injector Test Harness Adapter

A fuel injector balance test determines if the multiport fuel injection (MFI) system is functioning correctly from a fluid (gasoline) and electrical/mechanical (fuel injectors) perspective. To perform this test, follow the procedure below:

Attach Fuel Pressure Gauge

1. Relieve fuel system pressure. Refer to "Fuel System Pressure Relief Procedure" in this section.

2. Remove one bolt and fuel feed hose bracket from bottom of intake manifold.

3. Remove one bolt and fuel feed hose from fuel rail.

4. Install J39802 with gaskets and fuel feed hose to fuel rail.

Tighten
^ J39802 bolt to 29 Nm (22 lb-ft).

5. Connect J34730-1A to J39802.

6. Reconnect negative (-) battery cable.

Tighten
^ Negative (-) battery cable-to-negative (-) battery cable terminal retainer to 15 Nm (11 lb-ft).

INJECTOR BALANCE TEST

1. Disconnect the four fuel injector electrical connectors.

2. Turn the ignition switch to "ON" and momentarily connect a jumper between DLC terminals "+B" and "Fp".

3. Install one end of J34730115 to a fuel injector's terminals and the other end to J34730-3A.

4. Connect J34730-3A to the battery.

5. Set J34730-3A switch to one pulse and activate one time only.

Measure
Fuel Pressure while activating tester. Should drop to 179-234 kPa (26-34 psi) after tester is activated. If pressure is not within specifications, replace faulty fuel injector(s).

6. Repeat Steps 2 through 5 on the remaining fuel injectors.

7. Turn ignition switch to "LOCK" and reconnect all fuel injector electrical connectors.

8. Relieve fuel system pressure. Refer to "Fuel System Pressure Relief Procedure" in this section.

9. Remove one bolt and J39802 and J34730-1A from fuel rail.

10. Using two new gaskets, reconnect fuel feed hose to fuel rail; secure with one bolt.

Tighten
^ Fuel feed hose bolt to 29 Nm (22 lb-ft).

11. Reconnect fuel feed hose bracket to intake manifold; secure with one bolt.

Tighten

^ Fuel feed hose bracket bolt to 10 Nm (89 lb-in).

12. Reconnect negative (-) battery cable.

Tighten

^ Negative (-) battery cable-to-negative (-) battery cable terminal retainer to 15 Nm (11 lb-ft).

13. Turn ignition switch to "ON" and momentarily connect a jumper between DLC terminals "+B" and "Fp." Check for any fuel leaks.