Do not over tighten the rail. It will break. It doesnt require much torque. Just enough to seal. I've head of a few people break thier rails by overtightening the mounting bolts.
Fuel injection systems remain under pressure, even after the engine has been turned OFF. The fuel system pressure must be relieved before disconnecting any fuel lines. Failure to do so may result in fire and/or personal injury.
1. Disconnect negative battery cable.
2. Release the fuel system pressure.
3. Remove the engine cover from the top of the intake manifold plenum.
4. Disconnect the accelerator cable and speed control cable from the throttle arm.
5. Disconnect the power brake booster hose and remove the throttle cable bracket from the manifold.
6. Separate the electrical connectors from the idle air control motor and the intake air temperature sensor.
7. Disconnect the vacuum hose from the Manifold Tuning Valve (MTV).
8. Detach the electrical connectors from the Manifold Absolute Pressure (MAP) sensor and the throttle position sensor.
9. Disconnect the throttle body purge hose, PCV air hose and idle air control motor supply hose (part of the air inlet plenum). Remove the air inlet plenum from behind the manifold.
10. Disconnect the PCV hose and vacuum hoses from the intake manifold.
11. Remove the EGR tube mounting bolts at the intake manifold plenum and discard the gaskets. Remove the lower EGR mounting bolts located at the EGR valve.
12. Remove the support bracket mounting bolts on each side of the plenum. Remove the intake plenum mounting bolts.
The intake manifold plenum uses 2 different length bolts. Take note of their position and make sure they are installed in the same location during installation.
13. Remove the intake manifold plenum from the intake manifold. Discard the old gasket. Cover the intake manifold openings.
14. At the fuel rail, push the quick-connect fitting toward the fuel tube while pushing in the built-in disconnect tool using Special Quick-Connect Fitting Tool 6751 or equivalent. Disconnect the fitting from the fuel rail by slightly turning the fitting while applying downward pressure on Tool 6751. Be sure to wrap shop towels around the hoses to catch any fuel spillage.
15. Connect Special Fuel Gauge Adapter 6631 or exact equivalent, to the fuel supply tube end of the fuel rail. Connect fuel hose 6668 or exact equivalent, to the fuel return tube end of the fuel rail.
16. Place the other end of fuel hose 6668 into an approved gasoline container.
17. Drain the gasoline from the fuel rail. To purge the fuel from the fuel rail, spray a maximum of 55 psi (379 kPa) of compressed air into the end of adapter 6631.
The fuel rail must be void of gasoline prior to injector removal. If the fuel rail is not drained, the gasoline in the rail will enter the engine cylinders when the injectors are removed.
18. Tag all injector harness connectors noting cylinder location for reference during assembly. Detach the harness connectors from each injector.
19. Remove the vacuum hose from the fuel pressure regulator.
20. Remove the fuel rail mounting bolts and the injector clamp screw. Slide the injector clamp toward the rear of the engine, then lift the clamp off the rail.
21. Install the fuel rail mounting bolts finger-tight only.
22. Using a flat tipped tool, pry the fuel injector out of the fuel rail. Ensure the upper and the lower O-rings were removed with the injector. If not, remove them from the injector well in the fuel rail.
23. Lightly lubricate the O-rings with clean engine oil. Install the injector making sure to align the notch on the injector with the alignment tab on the fuel rail.
24. Remove the fuel rail mounting bolts. Install the fuel injector clamps.
25. Install the fuel rail using new gasket, and secure with retainers tightened to 8 ft. lbs. (11 Nm).
26. Reconnect the fuel supply and return tubes to the fuel rail. Be sure that the black plastic release ring to the quick-connect fitting is in the OUT position. Place tool 6751 or equivalent under the largest diameter of the quick-connect fitting.
27. Pull the disconnect tool toward the fuel rail until the quick-connect fitting clicks into place. Place the special tool between the shoulder of the built-in disconnect tool and top of the quick-connect fitting, then inspect the security of the fitting by applying a slight downward force against the fitting. It should be locked in place.
28. Attach the electrical harness connectors to the injectors making sure of correct location.
29. Install the intake manifold plenum with a new gasket in place. Tighten mounting bolts in proper sequence to 21 ft. lbs. (28 Nm).
30. Install and tighten the support bracket bolts.
31. Attach the electrical connectors to the manifold absolute pressure sensor, throttle position sensor, idle air control motor and intake air temperature sensor.
32. Reconnect the vacuum hose to the manifold tuning valve motor.
33. Install the EGR tube. Rotate the throttle lever to the wide-open position and reconnect the speed control and throttle cables.
34. Reconnect the PCV valve hose.
35. Install the air cleaner plenum and reconnect plenum hose. Reconnect the power brake booster hose to the fitting on the intake manifold plenum.
36. Reconnect the purge tubes to the fittings on the throttle body.
37. Install the cover on the intake manifold plenum.
38. Reconnect the negative battery cable.