Intake Manifold: Service and Repair

1. Disconnect battery ground cable, then drain cooling system.
2. Disconnect throttle, TV and cruise control cables from throttle body and brackets.
3. Remove bracket from plenum.
4. Disconnect electrical connectors from coolant temperature sensor, throttle position sensor, manifold air temperature sensor, idle air control and manifold absolute pressure sensor.
5. Disconnect air inlet duct from throttle body.
6. Disconnect and tag vacuum hoses from plenum and throttle body.
7. Disconnect heater hoses from throttle body.
8. Disconnect power brake unit vacuum hose from plenum fitting.
9. Remove plenum to runner attaching bolts, then remove plenum from engine.
10. Disconnect vacuum hose, then remove EGR solenoid from thermostat housing.
11. Remove EGR valve from intake manifold.
12. Remove injector wiring harness attaching bolts.
13. Relieve fuel system pressure as described under MAINTENANCE PROCEDURE/RELIEVING FUEL SYSTEM PRESSURE, then disconnect and cap fuel lines at fuel rail.
14. Remove fuel rail and injector assemblies.
15. Remove ignition distributor.
16. Disconnect upper radiator hose from thermostat housing.
17. Remove AIR pump brace.
18. Disconnect EGR valve pipe and position aside.
19. Disconnect hose from PCV valve and crankcase vent tube from intake manifold.
20. Remove intake manifold attaching bolts and intake manifold.
21. Ensure gasket surfaces are clean and dry, then install gaskets on cylinder head with blocked openings toward rear of engine.
22. Bend gasket tabs flush with front face with cylinder head, then apply a .2 inch bead of RTV sealer to front and rear ridges of cylinder block.
23. Apply sealant 1052080 or equivalent to manifold bolts.

Fig. 2 Intake Manifold Bolt Tightening Sequence:

24. Install manifold and torque bolts to specifications in sequence shown in Fig. 2, then reverse remaining procedure to complete installation.