Lower

1. Relieve fuel system pressure.
2. Disconnect battery ground cable, then remove upper intake manifold.
3. Disconnect fuel supply and return lines from fuel injection supply manifold.
4. Disconnect engine control sensor wiring from fuel injectors and valve cover studs. Position wiring aside.
5. Disconnect vacuum supply line from fuel pressure regulator and Intake Manifold Runner Control (IMRC) vacuum solenoid. Position line aside.
6. If necessary, remove fuel injection supply manifold and fuel injectors from lower intake manifold.
7. If necessary, remove IMRC vacuum solenoid from lower intake manifold.

Fig. 6 Lower intake manifold bolt removal sequence:

8. Remove lower intake manifold to cylinder head bolts in sequence.

Fig. 7 Lower intake manifold replacement:

9. Remove lower intake manifold from cylinder heads, then intake manifold gaskets from cylinder heads. Discard gaskets.
10. Reverse procedure to install, noting following:
a. Verify IMRC vacuum solenoid and plate operation using hand vacuum pump. Install new intake manifold gaskets.

Fig. 8 Intake manifold bolt tightening sequence:

b. Torque lower intake manifold bolts in sequence, to 5.9-8.8 ft lb.