Fuel Pressure: Testing and Inspection

Installing Fuel Pressure Gauge:

FUEL SYSTEM PRESSURE TEST
A fuel system pressure test is a part of several diagnostic charts and symptoms checks. To perform this test, use the following procedure.

TOOLS REQUIRED
J 34730-1 Fuel Pressure Gage
J 37746 Fuel Gage Adapter

PROCEDURE
1. Relieve fuel system pressure. Refer to Fuel Pressure Relief Procedure under Service and Repair. Service and Repair
2. Raise and suitably support vehicle.
3. Remove fuel filter inlet hose plug.
4. Install a J 37746 to fuel filter inlet union bolt.
5. Install a J 34730-1 to J 37746.
6. Lower vehicle.
7. Reconnect negative (-) battery cable. Tighten Negative (-) battery cable-to-negative (-) battery terminal retainer to 15 Nm (11 lb. ft.).
8. Start engine and idle at normal operating temperature.
9. Check fuel pressure as follows:
^ Idling - 240-280 kPa (34-41 psi).
^ Engine not running, ignition switch in the "ON" position - 240-280 kPa (34-41 psi).
^ Within one minute with engine not running, ignition switch in the "ON" position - pressure should hold at about 172 kPa (25 psi).

NOTE: If pressure is not within specification, refer to the On-Board Diagnostic System Check. Testing and Inspection

10. Relieve fuel system pressure. Refer to Fuel Pressure Relief Procedure.
11. Raise and suitably support vehicle.
12. Disconnect J 34730-1 and J 37746 from fuel filter. Use a shop towel to catch any remaining fuel that may leak.
13. Install fuel filter inlet hose plug.
14. Lower vehicle.
15. Connect negative (-) battery cable. Tighten Negative (-) battery cable-to-negative (-) battery terminal retainer to 15 Nm (11 lb ft).
16. Turn ignition switch to "ON" and then back to "LOCK" to pressurize the fuel system. Check for any fuel leaks.