Disconnect electrical connectors at air bypass valve, throttle sensor and EGR position sensor.
Disconnect throttle linkage at throttle ball. Disconnect AOD transmission
linkage from throttle body. Remove two bolts securing throttle linkage bracket to intake. Position bracket with cables out of way.
CAUTION: When disconnecting throttle cable from ball stud and pry slowly. Pulling by hand may damage the cable.
Disconnect upper intake manifold vacuum fitting connections by disconnecting all vacuum lines to vacuum tree, vacuum lines to EGR valve, and vacuum line to fuel pressure regulator.
Disconnect PCV system by disconnecting hose from fitting on rear of upper manifold.
Remove canister purge line(s) from fitting(s) on throttle body.
Disconnect water heater lines from the throttle body.
Disconnect EGR tube from EGR valve by removing flange nut.
Remove bolt from upper intake support bracket to upper manifold.
Remove six upper intake manifold retaining bolts.
Remove upper intake and throttle body as an assembly from lower intake manifold.
Clean and inspect the mounting faces of the lower and upper intake manifolds.
Position new gasket on lower intake mounting face. The use of alignment studs may be helpful.
Install upper intake manifold and throttle body assembly to lower manifold making sure gasket remains in place (if alignment studs aren't used).
Install six upper intake manifold retaining bolts and tighten to 16-24 Nm (12-18 ft-lbs) .
Install upper intake support bracket to upper manifold attaching bolt.
Install EGR tube.
Install canister purge lines to fittings on throttle body.
Connect water heater lines to the throttle body.
Connect PCV hose to rear of upper manifold.
Connect vacuum lines to vacuum tree, EGR valve, and fuel pressure regulator.
Position throttle linkage bracket with cables to upper intake manifold. Install two attaching bolts and tighten to specification. Connect throttle cable and transmission cable to throttle body.
Connect electrical connectors at air bypass valve, TP sensor, and EGR position sensor.
NOTE: If lower intake manifold was removed, fill and bleed cooling system.