Intake Manifold: Service and Repair
Fig. 1 Auxiliary Jumper Cable:
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.
To release fuel pressure, refer to the Powertrain Management/Fuel System/Service and Repair/Pressure Release.
REMOVAL
1. Perform fuel system pressure release procedure before attempting any repairs.
2. Disconnect negative cable from auxiliary jumper terminal Fig. 1.
3. Remove Air inlet Resonator.
4. Disconnect the fuel supply line quick connect at the fuel tube assembly. Refer to Fuel Line Fittings in Fuel System for procedure.
WARNING: Wrap shop towels around hose to catch any gasoline spillage.
5. 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.
6. Remove accelerator, kickdown and speed control cables from throttle lever and bracket. Refer to Fuel System, for procedures.
Fig. 2 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.2.
8. Disconnect vacuum hoses from throttle body Fig. 2.
Fig. 4 Manifold Absolute Pressure (MAP), Intake Air Temperature (IAT) Sensor Electrical Connectors:
Fig. 5 EGF Tube Assembly--Typical:
9. Disconnect Manifold Absolute Pressure (MAP), intake air temperature electrical connectors. Disconnect vapor and brake booster hoses Figs. 4 and 5.
10. Disconnect knock sensor electrical connector and disconnect wiring harness from tab located on the intake manifold.
11. Remove transmission to throttle body support bracket fasteners at the throttle body and loosen the fastener at the transmission end.
12. Remove EGR tube bolts at the valve and at the intake manifold Fig. 5. Remove tube from engine.
Fig. 8 Intake Manifold Tightening Sequence:
13. Remove the intake manifold support bracket Fig. 8.
14. Remove ten intake manifold fasteners and washer assemblies. Remove intake manifold.
CLEANING AND INSPECTION
Clean all mating surfaces.
Check for:
^ Cracked or distorted manifold.
^ Torn or missing 0-rings at the mating surface of the manifold Fig. 9.
INSTALLATION
1. Install new intake manifold gasket and manifold onto cylinder head and tighten fasteners to 11.9 Nm (105 in lb) in sequence shown in Figs. 6 and 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 Nm (200 in lb).
3. Connect PCV and brake booster hoses Fig. 4.
4. Inspect quick connect fittings for damage, replace if necessary Refer to Fuel System, for procedure. 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 Nm (200 in lb).
- Install transmission to throttle body support bracket and tighten to 11.9 Nm (105 in lb) 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.
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. 2.
10. Install accelerator, kick down and speed control cables to their bracket and connect them to the throttle lever. Refer to Fuel System, Throttle Body Installation for procedure.
11. Loose assemble the EGR tube onto valve and intake manifold finger tight Fig. 5.
- Tighten tube fasteners at the EGR valve first to 11 Nm (95 in lb)
- Then, tighten the intake manifold side fasteners to 11 Nm (95 in lb).
12. Connect negative cable from auxiliary jumper Fig. 1.
13. 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.