Deceleration Valve: Description and Operation

Fig. 78 Throttle closer system.:

Fig. 79 Throttle closer system.:

Fig. 80 Throttle closer system.:

Fig. 81 Throttle closer system.:

This system, Figs. 78 through 81, is used on CRX HF with 5 speed manual transmission. This system closes the throttle valve below its idle position when vehicle is decelerated under certain conditions.
When engine speed is above normal curb idle speed, vehicle speed is above 10 mph, clutch pedal is not depressed and manifold vacuum is high the throttle control valve is activated by the control unit. Vacuum is then routed through the throttle control solenoid valve and into the throttle closer, which retracts the carburetor throttle stop screw.