To replace the lower Intake Manifold, release the cooling system and supercharge. As the next step, remove the radiator inlet hose from the water outlet housing, even remove the exhaust gas recirculation (EGR) outlet pipe bolt and the egr outlet pipe from the lower Intake Manifold. Detach the engine coolant temperature (ECT) sensor electrical connector and remove the lower Intake Manifold bolts before removing the lower Intake Manifold, then the coolant bypass tube will also be released. The next step is removing the lower Intake Manifold seals and gaskets and if changing the manifold also removing the water outlet housing and Thermostat, as well as ect sensor. Check on the flatness on the inlet flanges and the mating surfaces on the lower Intake Manifold and the Intake Manifold bolt and bolt holes for any adhesive compound. Case of installation take note, if the ect sensor is removed, install using torque to 25 nm (18 ft. Lbs.). Then, if required, install the Thermostat, gasket and water outlet housing while tightening bolt and stud to 27 nm (20 ft. Lbs.). Replace the Intake Manifold gaskets and apply, gm p/n 12346286(Canadian P/N 10953472) or equivalent, on the extremities of the intake seals before putting the lower Intake Manifold seals. Prepare the bypass tube adjusted from the manifold opening and put the lower Intake Manifold in place (with lower Intake Manifold bolts followed by lower Intake Manifold bolts), tightening respectively from the center to the outside in sequence to 15 nm (11 ft. Lbs). Connect the ect sensor electrical connector back, connect the egr outlet pipe and its bolt, tighten it to 29 nm (21 ft. Lbs.). Finally replace the radiator inlet hose, the supercharger, top up the cooling system, and check for the fluid or vacuum leaks.