Section 1 (Cruise Control Systems): Operation: Actuator
WARNING: This page is about a different car, the 2000 Land Rover Range Rover, 2000 Land Rover Discovery, 1999 Land Rover Range Rover, and 1999 Land Rover Discovery. However, it is still accessible from the selected car via links, so may be relevant.
On all models, actuator provides a servo mechanism link between cruise control system and throttle linkage. Actuator is operated by vacuum, supplied by vacuum pump. Actuator position is changed by increasing or decreasing supplied vacuum by operating the vacuum pump, control valve and purge valve.