Upper Intake Manifold Assembly Replacement

Upper Manifold Assembly - Exploded View:

ECR Tube, Coolant And Fuel Pipe Retaining Bolts:

Upper Manifold Removal:

REMOVAL:

1. Disconnect the negative battery cable.
2. Partially drain the radiator. (The coolant hose at the upper manifold assembly will be removed later in the sequence).
3. Disconnect the throttle and cruise control cables from the throttle lever cam.
4. Remove the air cleaner assembly and air duct.
5. Disconnect the poser brake and PVC vacuum hoses from the upper manifold assembly.
6. Disconnect the electrical connectors from the IAC valve, TPS, and EGR valve.
7. Remove the retaining bolt, and EGR tube from the adapter (beneath the EGR valve).

CAUTION: To prevent damage to the EGR tube and/or misalignment of the mounting bracket, DO NOT attempt to bend this tube after removing the retaining bolt.

8. Remove the bolt retaining the coolant tube to the throttle cable bracket.
9. Remove the fuel pipe clip (retainer) bolt and clip.
10. Loosen the compression clamp on the upper manifold coolant inlet hose, slide the clamp down on the hose past the fitting.
11. Disconnect the crankcase vent hose from the front camshaft cover.
12. Disconnect the electrical connector from the Manifold Absolute Pressure (MAP) sensor.
13. Disconnect the vacuum hoses from the vacuum module (located beneath the MAP sensor).
14. Remove the engine identification cover attaching bolts, and cover.
15. Disconnect the spark plug wires from the rear cylinders.
16. Remove the upper manifold assembly, attaching bolts and rear mounting nuts.
^ Disconnect the inlet coolant hose.
^ Position the canister purge solenoid bracket off to one side.
17. Remove the coolant O-ring and upper manifold assembly gasket and discard.

Upper Manifold Assembly (ID):

NOTE: An eight digit part identification number is printed on a mylar label affixed to the plug on the plenum portion of the manifold. Refer to this number if servicing or replacement is required. Refer to the disassembled view for identification of parts during repair procedures.

DISASSEMBLY:

NOTE: A replacement upper manifold assembly includes the following component parts:
^ Throttle Position Sensor (TPS).
^ Idle Air Control (IAC) valve.

The following components are mounted on the upper manifold assembly but are not part of the replacement manifold assembly. These components have to be removed and transferred to the new assembly:
1. The EGR valve attaching bolts, EGR valve and EGR valve adapter.
2. The vacuum module attaching bolts and vacuum module with MAP sensor attached to it.
3. The throttle cable bracket attaching bolts, and throttle cable bracket.
4. The inlet coolant hose connection nipple.
5. The power brake booster vacuum pipe fitting.

CLEANING:

^ The upper manifold assembly and its components should not be cleaned or soaked in an immersion-type cleaner.

CAUTION: DO NOT use a cleaner that contains methyl ethyl ketone, an extremely strong solvent, and not necessary for the type of cleaning outlined below. Carburetor cleaner may be used to remove deposits. Refer to container instructions on the use of the product.

^ The upper manifold assembly contains the Throttle Position Sensor (TPS). Idle Air Control (IAC) valve, and internal throttle shaft sealed ball bearings. These components should NOT be subjected to strong solvent or cleaner bath. A chemical reaction will cause the parts containing rubber to swell, harden or distort, and the cleaner will also wash away the ball bearing grease or weaken its lubrication properties.
^ The throttle bore and valve deposits may be cleaned on-vehicle, using carburetor and a shop towel.
^ Use care in cleaning old gasket material from machined aluminum surfaces. Sharp tools may damage sealing surfaces.

ASSEMBLY:

Install the upper manifold transferred components to the new replacement upper manifold assembly:

1. EGR valve.
2. Install a new EGR valve-to-adapter gasket.
3. Install the EGR valve-adapter.
4. Install a new EGR valve-to-manifold gasket.
5. Install the EGR valve attaching bolts and tighten to 25 Nm (18 lb.ft).
6. Vacuum module with MAP sensor attached.
7. Install a new vacuum module gasket.
8. Install the vacuum module attaching bolts and tighten to 10 Nm (88 lb.in).
9. Install the inlet coolant hose connection nipple.
^ Wrap the screw threads with pipe sealant tape, or use an approved nonhardening pipe sealant.
^ Tighten the coolant hose connection nipple to 17 Nm (13 lb.ft).
10. Install the power brake booster vacuum pipe fitting.
^ Wrap the screw threads with pipe sealant tape, or use an approved nonhardening pipe sealant.
^ Tighten the power brake booster vacuum pipe fitting to 13 Nm (115 lb.in) minimum, then position the fitting to the left at a 45° angle.
11. Install the throttle cable bracket, and tighten the throttle cable bracket bolts to 25 Nm (18 lb.ft).

INSTALLATION:

1. Install a new coolant O-ring and new upper manifold gasket.
^ Lubricate the O-ring with clean ethylene glycol base antifreeze.
2. Position the upper manifold assembly over the gasket.
3. Connect the inlet coolant hose.
4. Install the upper manifold assembly bolts and tighten to 25 Nm (18 lb.ft).
5. Position the canister purge solenoid bracket over the manifold mounting stud.
6. Install the upper manifold assembly mounting nuts and tighten to 25 Nm (18 lb.ft).
7. Install the coolant hose compression clamp.
^ Slide the clamp over the coolant fitting.
8. Install the coolant tube to the throttle cable bracket bolt.
9. Install the fuel pipe clip (retainer) and bolt, tighten to 6.0 Nm (53 lb.in).

CAUTION: To prevent damage to the EGR tube and/or misalignment of the mounting bracket, DO NOT attempt to bend the tube while installing it.

10. Install the EGR tube and retaining bolt, tighten to 25 Nm (18 lb.ft).
11. Connect the electrical connectors to the IAC valve, TPS, and EGR valve.
12. Connect the power brake and PCV vacuum hoses to the upper manifold.
13. Install the air cleaner assembly and air duct.
14. Connect the throttle and cruise control cables to the throttle lever cam.
15. Install the spark plug wires to the rear cylinders.
16. Install the engine identification cover and attaching bolts.
17. Connect the vacuum hoses to the vacuum module (located beneath the MAP sensor).
18. Connect the electrical connector to the Manifold Absolute Pressure (MAP) sensor.
19. Install the crankcase vent hose to the tube on the front of the camshaft cover.
20. Add ethylene glycol base antifreeze to the radiator.
21. Connect the negative battery cable.
22. With the engine OFF, check to see that the accelerator pedal is free.
23. START the engine, check for coolant leaks.
24. The ECM will need to relearn to IAC valve pintle position following battery reconnection, refer to MAINTENANCE PROCEDURES/IDLE LEARN PROCEDURE.