GM 91176420 Manifold,Intake (On Esn)

The intake manifold removal procedure begins by relieving the fuel injection system pressure first and later disconnecting the negative battery cable. Also, drain the cooling system and remove the air intake duct between the air cleaner housing and the throttle body. Each electrical connection should be labelled prior to disconnecting it carefully as such include those for Exhaust Gas Recirculation (EGR) valve connector, Idle Air Control (IAC) valve connector, Throttle Position (TP) sensor connector, Evaporative Emissions (EVAP) canister purge valve connector, ground terminal on the intake manifold, Manifold Differential Pressure (MDP)/Manifold Absolute Pressure (MAP) sensor connector. Some of these hoses include brake booster hose, PCV hose, fuel pressure regulator vacuum hose, canister purge hose, vacuum hose, coolant hoses and breather hose from throttle body. Disconnect throttle cable, and if equipped with automatic transmissions, disconnect throttle valve cable too. The throttle body must be removed along with fuel rail and fuel injectors in case you want to replace intake manifold. Do not forget to take off two intake manifold stiffener plates as well as detach coolant pipe from the intake manifold next. Furthermore there is a need to remove mounting bolts and nuts for intake manifold before carefully taking it out of engine by avoiding prying it apart between gasket sealing surfaces or tapping on their throttle bodies under no circumstances. Then completely clean mating surfaces and install the manifold together with a new gasket-tighten bolts and nuts slowly in a crisscross pattern. Finally install remaining components back in reverse order; add coolant; run engine; check for leaks or problems.