California Models

Actuation of the throttle controller is by the throttle control valve. See Fig 2. When the manifold vacuum exceeds a preset value, the valve opens and the vacuum is introduced into the throttle opener.

Fig 1: 1978-79 Throttle Control System (With Throttle Opener System)

Courtesy of AMERICAN HONDA MOTOR CO., INC.

When intake manifold vacuum becomes less than the preset value, the valve is closed and the remaining vacuum in the throttle controller and the throttle control valve is returned to atmospheric pressure by the orifice.

Fig 2: Throttle Control Valve (Calif.)

Courtesy of AMERICAN HONDA MOTOR CO., INC.