Start by disconnecting the negative battery terminal and removing the air cleaner housing, mass airflow sensor, and ducting. Disconnect the throttle cable(s), air intake ducting, and any attached wiring connectors. Disconnect the electrical connectors from the oil pressure and temperature switches, unclip the fuel lines, and remove the guide tube. Remove the cable duct mounting screws/nuts and the throttle body from the intake manifold. When installing, ensure the O-ring seal is in good condition and tighten the bolts securely. Reconnect the throttle body wiring connector. For M54 engines, install the wiring connector. If a new throttle body is installed, reset the ECM values. For M54 and M56 engines, disconnect the negative battery cable, remove the air cleaner housing, and disconnect the wiring connector, vacuum hose, and intake ducting. Remove the DISA adjustment unit and the suction jet tube. Disconnect the intake ducting and the idle speed control valve wiring connector.