Fuel Rail: Service and Repair

REMOVAL:

1. Disconnect negative battery terminal.
2. Disconnect hoses:
a. Water hose from water bypass pipe
b. Vacuum hoses from throttle body
c. ISC Valve hoses from throttle body
d. Vacuum hose from FPR
3. Disconnect TPS and ISC Valve connectors.
4. Disconnect accelerator connecting rod.
5. Remove No.1 air cleaner hose.

Removing Air Cleaner Pipe:

6. Disconnect the six hoses from the ISC pipe and remove the ISC pipe.
7. Remove PCV pipe with hoses.
8. Remove intake air connector from top of engine.
9. Remove the Throttle Body from the intake plenum. Refer to THROTTLE BODY for proper procedure.
10. Disconnect the No.2 water bypass hose from the ISC Valve.

Removing No.2 Water Bypass Hose From ISC Valve:

11. Remove the Idle Speed Control (ISC) Valve from the intake plenum.

Removing ISC Valve:

12. Disconnect the injector connectors.
13. Remove Cold Start Injector fuel tube from the engine.

Disconnecting Fuel Delivery Tube From Fuel Rail:

14. Remove the Fuel Pressure Pulsation Damper and gaskets from the fuel inlet pipe.

Removing Fuel Presure Pulsation Damper:

15. Disconnect and remove the No.2 fuel return pipe from the Fuel Pressure Regulator (FPR).

Removing No.2 Fuel Pipe From Fuel Pressure Regulator:

16. Loosen the lock-nut and remove the Fuel Pressure Regulator from the fuel rail.

Fuel Pressure Regulator (FPR):

17. Remove the three mounting bolts and lift the fuel rail along with the six injectors from the engine.

Fuel Rail:

CAUTION: Be careful that the injectors do not drop from the Fuel Rail. Damage to the injector tip could result.

18. Remove the six insulators and three spacers from the cylinder head.
19. When the Fuel Rail is safely over a workbench, pull the injectors from the Fuel Rail.

INSTALLATION:

***UPDATED BY TSB# EN91-006, MAY 24, 1991

1. Install new grommet and O-ring on each removed injector.

Fuel Injector O-Ring:

2. Apply a light coat of gasoline to the O-ring to ease insertion into the Fuel Rail.
3. With a twisting motion, install each injector into the Fuel Rail until fully seated. Carefully check proper alignment to prevent fuel leaks.

Correct Installation Of Injector To Fuel Rail:

4. Place six new insulators and three spacers in position on the cylinder head.

Installing Fuel Rail Insulators And Spacers:

5. Carefully install the Fuel Rail with injectors on the cylinder head.
6. Start the three mounting bolts, but do not tighten. Rotate each injector to ensure that there is no binding of the sealing parts.

Installing Fuel Rail With Injectors:

7. If the injectors do not rotate smoothly, recheck the O-rings for correct installation.

Correct Installation Of Fuel Injector Components:

8. Position injector connector sockets facing up.
9. Torque the three mounting bolts to 13 ft.lbs. (18 N-m).

Fuel Rail:

10. Screw the Fuel pressure Regulator into the fuel rail using a new O-ring. Lightly coat the O-ring with gasoline to ease insertion into the fuel rail.
11. Tighten the lock-nut to 18 ft.lbs. (25 N-m) and observe proper positioning of the vacuum nipple.

Correct Alignment Of FPR:

12. Install the No.2 fuel return pipe to the intake manifold with two clamp bolts.
13. Connect union bolt to the Fuel Pressure Regulator with new gaskets and torque to 18 ft.lbs. (25 N-m). Connect the hose to the other end of the return pipe.
14. Connect the No.1 inlet fuel tube to the fuel filter and torque Fuel Pressure Pulsation Damper to 29 ft.lbs. (39 N-m), if using copper gaskets and 20 ft.lbs. (26 N-m), if using tin plated gaskets.
15. Connect the cold start injector fuel pipe to the Cold Start Injector and the fuel rail. If copper gaskets are used, torque the Cold Start Injector union bolt to 13 ft.lbs. (18 N-m) or if tin plated gaskets are used, torque to 8 ft.lbs. (11 N-m). DO NOT overtighten the union bolts.
16. Torque the fuel rail union bolt to 22 ft.lbs. (29 N-m), if using copper gaskets and 23 ft.lbs. (31 N-m), if using tin plated gaskets.
17. Connect injector connectors.
18. Install ISC Valve on intake plenum. Torque mounting bolts to 9 ft.lbs. (13 N-m).

Installing ISC Valve:

19. Install Throttle Body on intake plenum. Refer to THROTTLE BODY for proper procedure.
20. Install intake air connector to top of engine.
21. Install PCV pipe with hoses.
22. Connect the six hoses to the ISC pipe and install the ISC pipe.
23. Connect No.1 air cleaner hose.
24. Connect accelerator connecting rod.
25. Connect TPS and ISC Valve connectors.
26. Connect hoses:
a. Water hose to water bypass pipe
b. Vacuum hoses to throttle body
c. ISC Valve hoses to throttle body
d. Vacuum hose to FPR
27. Reconnect the negative battery terminal.
28. Start engine and check for fuel leaks.