To remove the throttle body on 6-cylinder engine models, first depressurise the fuel system, then disconnect the battery negative lead and position it away from the terminal. Remove the air cleaner assembly, unbolt the throttle linkage bracket on the air flow sensor if applicable, and disconnect the linkage return spring(s) on the throttle body along with the linkage connecting rod. If applicable, disconnect the cruise control actuator linkage from the throttle valve lever and disconnect the vacuum hose(s) at the throttle body, labeling each hose carefully. Unplug the throttle valve switch wiring at the harness connector, unscrew the nuts securing the throttle body to the inlet manifold, and slacken the large hose clip on the rubber connecting sleeve between the throttle body and the airflow sensor. For 6-cylinder engine models, remove the entire fuel distributor unit from the inlet manifold. Unscrew the two nuts securing the airflow sensor to its rubber mountings at the throttle linkage end, unscrew the fuel return line union nut at the rear of the fuel pressure regulator, and disconnect the return line while being prepared for fuel spillage. Carefully lift the airflow sensor enough to allow the throttle body to be removed, then unscrew the securing bolts and lift the throttle body from the inlet manifold. For 6-cylinder engine models, recover the throttle body gasket, while for 4-cylinder engine models, cut out and remove the inlet manifold gasket centre section at the throttle body contact area, taking care to avoid scoring the mating surface. To refit the throttle body, follow the removal procedure in reverse, ensuring that if the throttle body is renewed, a new throttle switch is also fitted, and for 6-cylinder engine models, a new throttle body gasket is used. For 4-cylinder engine models, cut the centre section from a new inlet manifold gasket and lay it in position over the throttle body contact area. Tighten the throttle body securing bolts to the specified torque, ensure that the vacuum hoses are refitted correctly, and upon completion, check and adjust the engine idle speed if necessary.