DECEL Valve System: Description

Three deceleration valve systems are used. The conventional decel valve system (which is used on the 1975-77 2300 cc engine only) and the speed modulated decel valve system (which is used on the 1975-76 2800 cc V6 engine only). The third type is called A/C modulated decel valve system and is used on 1977 2800 V6 with 2150 2-Bbl. carb. only.

The decel valve supplies additional air/fuel mixture to engine during periods of deceleration (high intake manifold vacuum when throttle valve is closed). The conventional decel valve is controlled by engine vacuum. The speed modulated decel valve is controlled by vehicle speed through a connection to the speedometer cable.