Intake Manifold: Service and Repair

1. Disconnect battery(s).
2. Drain cooling system, then remove air cleaner and intake duct assembly.
3. Remove ignition coil mounting bracket and disconnect high tension lead from ignition coil.
4. On 1991-93 models, remove Thermactor system from righthand intake manifold.
5. On all models, remove external EGR tube and both thermactor exhaust air supply manifold tubes.
6. Disconnect upper radiator hose from engine and the heater hoses from intake manifold and water pump and position aside. Loosen water pump bypass hose at intake manifold.
7. Disconnect PCV valve hose from right rocker arm cover.
8. Disconnect and tag all vacuum lines at rear of intake manifold.
8. Disconnect ignition wires from spark plugs, then remove distributor cap and wires as an assembly.
10. Remove distributor.
11. Disconnect accelerator linkage and transmission kickdown linkage from throttle body, then remove bolts holding accelerator linkage cable and position aside.
12. On models equipped with speed control, remove speed control linkage bracket from intake manifold and disconnect from throttle body
13. On all models, disconnect fuel line from fuel rail.
14. Disconnect electrical connector from main wiring harness. Wiring harness and manifold are to be removed as an assembly.
15. Remove throttle body heater hose from water pump and intake manifold heater outlet connection.
16. Remove intake manifold attaching bolts and nuts, then the intake manifold and throttle body as an assembly. If necessary, carefully pry manifold away from cylinder heads. Do not damage gasket sealing surfaces.

Fig. 15 Intake manifold installation:

Fig. 16 Intake manifold bolt tightening sequence:

17. Reverse procedure to install. Apply sealer as shown in Fig. 15. Tighten manifold attaching bolts in 3 steps as shown in Fig. 16:
1. 8-12 ft-lbs
2. 12-22 ft-lbs
3. 22-35 ft-lbs