Intake Manifold Replacement

WARNING: Release fuel system pressure before servicing fuel system components. Service vehicles in well ventilated areas and avoid ignition sources. Never smoke while servicing the vehicle.

Fig. 1 Fuel Pressure Test Port:

Fig. 2 Releasing Fuel Pressure:

FUEL SYSTEM PRESSURE RELEASE PROCEDURE
1. Disconnect negative cable from battery.
2. Remove fuel filler cap.
3. Remove protective cap from fuel pressure test port on fuel rail (Fig. 1).
4. Place open end of fuel pressure release hose tool No. C-4799-1, or equivalent, into a suitable gasoline container, then connect other hose end to fuel pressure test port. Fuel pressure should bleed off through hose into container.

REMOVAL
1. Perform fuel system pressure release procedure before attempting any repairs.
2. Disconnect negative battery cable.
3. Disconnect the fuel supply line quick connect at the fuel tube assembly.

WARNING: Wrap shop towels around hose to catch any gasoline spillage.

4. Remove fuel rail assembly attaching screws and remove fuel rail assembly from engine. Cover injector holes with suitable covering.

CAUTION: Do not set fuel injectors on their tips, damage may occur to the injectors.

Fig. 3 Fresh Air Duct To Throttle Body Assembly:

5. Remove fresh air duct and upper air filter housing (Fig. 3)
6. Remove accelerator, kickdown and speed control cables from throttle lever and bracket.

Fig. 4 Idle Air Control (IAC) Motor And Throttle Position Sensor (TPS) Wiring Connectors And Vacuum Hose Connection.:

7. Disconnect Idle Air Control (IAC) motor and throttle position sensor (TPS) wiring connectors (Fig. 4).
8. Disconnect vacuum hoses from throttle body (Fig. 4).

Fig. 5 Intake Manifold Electrical, Vacuum Hose Connections And Knock Sensor Electrical Connector:

9. Disconnect Manifold Absolute Pressure (MAP), and intake air temperature electrical connectors. Disconnect vapor and brake booster hoses (Fig. 5).
10. Disconnect knock sensor electrical connector and disconnect wiring harness from tab located on the intake manifold (Fig. 5).
11. Disconnect electrical connector from starter relay.
12. Remove transmission to throttle body support bracket fasteners at the throttle body and loosen fastener at transmission end.
13. Remove throttle body.

Fig. 6 EGR Tube Assembly:

14. Remove EGR tube bolts at the valve and at the intake manifold (Fig. 6). Remove tube from engine.

Fig. 8 Intake Manifold Tightening Sequence:

15. Remove the intake manifold to inlet water tube support fastener (Fig. 8).
16. Remove 9 intake manifold screw and washer assemblies and 1 lock nut. Discard the fasteners. Remove intake manifold.

Fig. 7 Intake Manifold O-rings:

INSPECTION
Check for:
- Inspect manifold for cracks or distortions.
- Check for torn or missing O-rings at the mating surface of the manifold (Fig. 7).

NOTE: Before installing manifold. Clean all mating surfaces. Replace all seals, with new seals. All intake manifold fasteners and washers are to be discarded and NEW fasteners and washers are to be used.

INSTALLATION
1. Install intake manifold onto cylinder head and tighten fasteners to 11.9 N.m (105 in. lbs.) in sequence shown in (Fig. 8).
2. Remove covering from fuel injector holes and insure the holes are clean. Install fuel rail assembly to intake manifold. Tighten screws to 23 N.m (200 in. lbs.).
3. Connect PCV and brake booster hoses (Fig. 5).
4. Inspect quick connect fittings for damage, replace if necessary. Lube tube with clean 30w engine oil, Connect fuel supply hose to fuel rail assembly Check connection by pulling on connector to insure it locked into position.
5. Install throttle body Tighten fastener to 22 N.m (200 in. lbs.). Install transmission to throttle body support bracket and tighten to 11.9 N.m (105 in. lbs.) at the throttle body first. Next tighten the bracket at the transmission.
6. Connect manifold absolute pressure (MAP) and intake air temperature sensor wiring connectors (Fig. 5).
7. Connect knock sensor electrical and starter relay connectors. Connect wiring harness to intake manifold tab.
8. Connect Idle Air Control (IAC) motor and Throttle Position Sensor (TPS) wiring connectors (Fig. 4).
9. Connect vacuum hoses to throttle body (Fig. 4).
10. Install accelerator, kickdown and speed control cables to their bracket and connect them to the throttle lever.
11. Loosely assemble the EGR tube onto valve and intake manifold finger tight (Fig. 6). Tighten tube fasteners at the EGR valve first to 11 N.m (95 in. lbs. then, tighten the intake manifold side fasteners to 11 N.m (95 in. lbs.).
12. Install fresh air duct to air filter housing. Tighten clamp to 3 N.m (30 in. lbs.) (Fig. 3).
13. Connect negative battery cable.
14. With the DRB scan tool use ASD Fuel System Test to pressurize system to check for leaks.

CAUTION: When using the ASD Fuel System Test, the Auto Shutdown (ASD) relay will remain energized for 7 minutes or until the ignition switch is turned to the OFF position, or Stop All Test is selected.