Fuel Rail: Service and Repair
REMOVALWARNING: THE FUEL SYSTEM IS UNDER A CONSTANT PRESSURE (EVEN WITH ENGINE TURNED OFF). BEFORE SERVICING FUEL RAIL ASSEMBLY, FUEL SYSTEM PRESSURE MUST BE RELEASED.
To release fuel pressure, refer to Fuel System Pressure Release Procedure in this group.
Fig. 19 Fuel Rail Assembly - 3.9/5.2/5.9L Engine - Typical:
CAUTION: The left and right fuel rails are replaced as an assembly. Do not attempt to separate rail halves at connecting hose (Fig. 19). Due to the design of this connecting hose, it does not use any clamps. Never attempt to install a clamping device of any kind to hose. When removing fuel rail assembly for any reason, be careful not to bend or kink connecting hose.
1. Remove negative battery cable at battery.
2. Remove air cleaner.
3. Perform fuel pressure release procedure.
4. Remove throttle body from intake manifold. Refer to Throttle Body removal in this group.
Fig. 20 A/C Compressor Support:
5. If equipped with air conditioning, remove A-shaped A/C compressor-to-intake manifold support bracket (three bolts) (Fig. 20).
Fig. 21 Remove/Install Injector Connector:
6. Disconnect electrical connectors at all 8 fuel injectors. To remove connector refer to (Fig. 21). Push red colored slider away from injector (1). While pushing slider, depress tab (2) and remove connector (3). from injector. The factory fuel injection wiring harness is numerically tagged (INJ 1, INJ 2, etc.) for injector position identification. If harness is not tagged, note wiring location before removal.
7. 3.9L (V-6) engine only: Disconnect electrical connector at intake manifold air temperature sensor. Do not remove sensor.
8. Disconnect fuel tube (line) at side of fuel rail. Refer to Quick-Connect Fittings for procedures,
9. Remove remaining fuel rail mounting bolts.
10. Clean dirt/debris from each fuel injector at intake manifold.
11. Gently rock and pull left fuel rail until fuel injectors just start to clear intake manifold. Gently rock and pull right fuel rail until fuel injectors just start to clear intake manifold. Repeat this procedure (left/right) until all fuel injectors have cleared intake manifold.
12. Remove fuel rail (with injectors attached) from engine.
Fig. 22 Fuel Injector:
Fig. 23 Injector Retaining:
13. Remove clip(s) retaining injector(s) to fuel rail (Fig. 22) or (Fig. 23).
INSTALLATION
WARNING: THE FUEL SYSTEM IS UNDER A CONSTANT PRESSURE (EVEN WITH ENGINE TURNED OFF). BEFORE SERVICING FUEL RAIL ASSEMBLY, FUEL SYSTEM PRESSURE MUST BE RELEASED.
To release fuel pressure, refer to Fuel System Pressure Release Procedure in this group.
CAUTION: The left and right fuel rails are replaced as an assembly. Do not attempt to separate rail halves at connecting hose (Fig. 19). Due to the design of this connecting hose, it does not use any clamps. Never attempt to install a clamping device of any kind to hose. When removing fuel rail assembly for any reason, be careful not to bend or kink connecting hose.
1. Apply a small amount of clean engine oil to each fuel injector O-ring. This will help in fuel rail installation.
2. Install injector(s) and injector clip(s) to fuel rail.
3. Position fuel rail/fuel injector assembly to injector openings on intake manifold.
4. Guide each injector into intake manifold. Be careful not to tear injector O-ring.
5. Push right fuel rail down until fuel injectors have bottomed on injector shoulder. Push left fuel rail down until fuel injectors have bottomed on injector shoulder.
6. Install fuel rail mounting bolts.
7. Connect electrical connector to intake manifold air temperature sensor.
8. Connect electrical connectors at all fuel injectors. To install connector, refer to (Fig. 21). Push connector onto injector (1).and then push and lock red colored slider (2). Verify connector is locked to injector by lightly tugging on connector.
9. Install A/C support bracket (if equipped).
10. Install throttle body to intake manifold. Refer to Throttle Body installation in this group.
11. Install fuel tube (line) at side of fuel rail. Refer to Quick-Connect Fittings for procedures.
12. Install air cleaner.
13. Connect battery cable to battery.
14. Start engine and check for leaks.