First of all, turn the ignition off and eliminate the connection between the negative terminal of the battery and the vehicle's frame. Then, next proceed to take out the engine cover and the air intake duct. Remove the PCV hose, ground strap, electrical connectors and vacuum lines from the upper intake manifold connecting them as you remove them and moving aside the wiring harnesses. Remove the throttle body by unplugging the TPS and IAC, then loosening the bolts that hold it in place, and if you are going to reuse it clamp off the coolant hoses before you remove them. Remove the upper intake manifold brace, if installed, then remove the bolts on the valve EGR then pull the valve EGR back. Take off the bolts that connect the upper intake manifold to the lower intake manifold then slightly lift up the upper intake manifold to clear the throttle body and the lower intake manifold. Remove the coolant from the cooling system and, using appropriate tools and perhaps a wrench, remove the terminals of the fuel injectors' wires and that of the fuel line on the fuel rail. It is possible to carry out the removal of the intake manifold together with the injectors and fuel rails if necessary, or do it independently. Unfasten any more connectors of the lower manifold, then extract the mounting bolts one by one starting from the other end to unhook the lower intake manifold off the engine; do not pry between the gasket surfaces as this will cause damage. Speaking of the most significant changes in the structure of the main node, one should check its surface and if it is heavily deformed, it is better to replace it. For installation, scraping is used to remove any deposits of gasket material and sealant on the lower intake manifold and cylinder heads, the use of brake system cleaner is used to clean the mating surfaces. new gaskets and position the lower intake manifold on the engine so that the gaskets do not shift while the bolts that hold the intake manifold are tightened down to the correct torque, it is usually done in three or four steps. Replace the existing gasket for the lower and upper intake manifolds before fitting the former on the latter; fasten the bolt in the required pattern while exerting the recommended amount of pressure on the intake manifold. Lastly, unscrew the radiator cap to add Coolant if necessary and resume the car to identify fuel, vacuum and Coolant leakages.