Intake Manifold Replacement - Lower

Intake Manifold Replacement - Lower (L36)

Removal Procedure

Notice: The two bolts which fasten the lower intake manifold to the cylinder head are accessible only after the upper intake is removed. The bolts are located in the right front and left rear corners of the lower intake manifold. Remove the upper intake manifold to service the lower intake.





1. Remove the upper intake manifold.
2. Remove the generator brace.
3. Remove the drive belt tensioner with mounting bracket and the heater water bypass inlet pipe.





4. Remove the exhaust gas recirculation (EGR) outlet pipe from the lower intake manifold.





5. Remove the radiator inlet hose from the water outlet housing.





6. Disconnect the engine coolant temperature (ECT) sensor electrical connector.





7. Remove the generator brace bracket bolts.
8. Remove the generator brace bracket.





9. Remove the evaporative emissions canister purge solenoid valve.





10. Remove the lower intake manifold bolts.
11. Remove the lower intake manifold.





12. Remove the lower intake manifold seals.





13. Remove the lower intake manifold gaskets.





14. If replacing the lower intake manifold, remove the water outlet housing bolt and stud, the water outlet housing, the gasket and the thermostat.
15. If replacing the lower intake manifold, remove the engine coolant temperature (ECT) sensor.
16. Inspect the flatness of inlet flanges.
17. Clean the lower intake manifold mating surfaces.
18. Clean the intake manifold bolts and bolt holes of adhesive compound.

Installation Procedure

Notice: Refer to Fastener Notice in Service Precautions.





1. If removed, install the engine coolant temperature (ECT) sensor.
- Tighten the engine coolant temperature (ECT) sensor to 25 Nm (18 ft. lbs.).
2. If removed, install the thermostat, the gasket, the water outlet housing.
3. Install the water outlet housing bolt and stud.
- Tighten the water outlet housing bolts and stud to 27 Nm (20 ft. lbs.).





4. Install the lower intake manifold gaskets.





5. Apply sealer GM P/N 12346286 or equivalent to the ends of the intake manifold seals.
6. Install the lower intake manifold seals.





7. Install the lower intake manifold.





8. Install the lower intake manifold bolts (1-12). Apply thread lock compound GM P/N 12345382 or equivalent to the two hidden bolts and ensure they are installed.
- Tighten the lower intake manifold bolts in sequence to 15 Nm (11 ft. lbs.).





9. Install the evaporative emissions canister purge solenoid valve.





10. Install the generator brace bracket.
11. Install the generator brace bracket bolts.
- Tighten the generator brace bracket bolts to 50 Nm (37 ft. lbs.).





12. Connect the engine coolant (ECT) temperature sensor electrical connector.





13. Install the radiator inlet hose to the water outlet housing.





14. Install the EGR outlet pipe to the lower intake manifold.
- Tighten the EGR outlet pipe bolt to 29 Nm (21 ft. lbs.).





15. Install the drive belt tensioner.
16. Install the generator brace.
17. Install the upper intake manifold.