Before unplugging the MI, the fuel pressure must be cut off and the air duct assembly should be discontinued, and the negative terminal of the battery should be disconnected. Remove the upper intake plenum and throttle body, disconnect IMRC vacuum and electrical connectors, fuel lines, fuel pressure regulator and injector connectors and drain the cooling system. Place a shop towel over the air intake openings to block dust from getting into the engine, and remove the upper radiator hose, and the heater hoses connected to the intake manifold. Remove the EGR valve vacuum hose and EGR tube fitting at the EGR valve; label and remove ECM vacuum and emissions hoses and wire harness connectors connected to the intake manifold. Tighten the intake manifold mounting bolts by a quarter turn at a time as many as possible until they can be removed with the hands; in all, there are fourteen of the bolts. If it is stuck to the cylinder heads, use the prybar to pull apart the gaskets, again, make sure that all bolts have been pulled out and do not pry between the engine block and the intake manifold as you will cause some damage. For installation, the mating surfaces of the cylinder heads, engine block and manifold must be clean, perhaps using gasket removal solvents. Pull off the old gasket with a gasket scraper, then wash the surface with lacquer thinner or acetone, and cover the lifter valley with shop rags to avoid contaminate. Take a tap and chase the threads in the bolt holes and blow with compressed air to remove any dirt. The surfaces of the gaskets should be checked before placing a 1/8-inch-wide bead of RTV sealant on the front and the rear of the block surface after which one of the rubber seals for the front and rear manifolds need to be put in place. Put a small amount of RTV at the locations where side gaskets are to abut the end seals, place the side gaskets at the cylinder heads, and check if openings are in the right position. Gently install the manifold in place while the sealant is still wet which will minimize distortion of the gaskets. The manifold bolts should only be lightly oiled and then screwed and tightened to the correct torque setting in turns. Last, turn on the engine and look for signs of oil and coolant leakage at the gasket joint of intake manifold.