The initial step of the throttle body procedure is given by the disconnection of the cable that is connected to the battery's negative terminal, where models with the Delco Loc II audio system feature a lockout function. Remove the connectors of the IAC valve, TPS, the vacuum hoses and the throttle cable, the breather hose and the air inlet duct. Before removing the bolts of the throttle body, the coolant should be drained and the coolant lines should be disconnected, the throttle body should also be detached. Fit in the new throttle body and the gasket by using the appropriate size of bolts and tighten them to the recommended degree. The rest of the process is the process of assembling. In case of the IAC valve, the electrical connector should be disconnected, the attaching screws to be unbolted and a new rubber O-ring must be installed after the washing of the special sealing surface. Ensure the pintle position is correct before whole assembly and fit a new O-ring with engine oil before fitting the IAC valve squarely. Replacement of the TPS requires the appointment of a dealer or repair shop with a scan tool for the correct adjustment. For the plenum on V6 and 1992 and later 2.2L engines and removal you have to: Pull the negative battery cable, remove vacuum hoses with their connectors and mark, remove the throttle cable bracket. EGR valve & throttle body have to be detached together with the plastic spark plug-wire shield and the plenum bolts. Undue care should be taken when removing the plenum; and the gaskets should be cleaned to remove any sign of the old gasket material before the new gaskets are fitted and the plenum replaced with bolts. The fuel rail on the other hand requires the negative battery cable to be removed, plenum if found to be removed and fuel lines disconnected by turning them around the backup wrench. Disconnect the injector electrical connect and unplug then take out the fuel rail bolts and then take out fuel rail with the injectors. Before servicing of the injectors clean the area around the injectors, then unlock the injector clip and pull out the injectors and should check and replace the O-ring seals if applicable. Fit new O-rings lubricated with engine drive, tighten the injectors by means of retainer clips and depending on a type of the engine unload necessary fittings and scews for the fuel pressure regulator in this Updated procedure all gaskets and seals must be replaced. Last, lubricate the injector O-ring seals and then install fuel rail and energize the fuel system for leaks. Mass Air Flow (MAF) sensor can be removed from the car by unscrewing the mounting screw, disconnecting the electrical connector and detaching the air duct before lifting the MAF sensor out of the car, though should be handled carefully should one intend to re-install it. Installation procedure is just the reverse of removal process.