Disconnecting the electrical connector at the throttle body and later reconnecting it will cause the engine management system to require the throttle valve closed position relearn procedure to be performed. To avoid having to perform this procedure during removal or installation of the plenum, unbolt the throttle body from the plenum with the connector in place and set the throttle body aside carefully. First, relieve the fuel system pressure and, with the engine cool, partially drain the coolant. Next, disconnect the cable from the negative terminal of the battery, then remove the air intake duct and the engine cover. After that, remove the throttle body from the front of the intake manifold, followed by the fuel rails and fuel injectors. Label and disconnect any hoses and harnesses that may be attached to the intake manifold. Loosen the intake manifold fasteners in the reverse order of the tightening sequence and remove the bolts and the manifold, which are accessible after the fuel rails and injectors are removed. To install the manifold, clean the mounting surfaces of the intake manifold and the ports on the
Cylinder Heads with lacquer thinner, removing all traces of the old gasket material or sealant. Install new gaskets on the intake manifold and position the manifold on the engine, ensuring there are eight individual gaskets for the manifold, one for each intake port. Following the recommended tightening sequence, tighten the fasteners in several steps to the specified torque. The remainder of installation is the reverse of the removal procedure. If the throttle body electrical connector was disconnected, perform the relearn procedures. If the coolant hoses were disconnected from the throttle body, check the coolant level and add if necessary. Finally, run the engine and check for fuel, vacuum, and coolant leaks.