Deceleration Control System: Description

Deceleration systems reduce HC emissions through the use various devices. On Colt and Colt Vista models a dashpot and a deceleration spark advance system consisting of an engine speed sensor and solenoid valve is used. On Ram-50 Pickups, air switching valve, coasting air valve and dashpot (all Man. Trans. models except Federal Pickups) are used.

Air switching valve cuts off fuel to by-pass holes and pilot outlet by supplying additional air to slow idle passage. Coasting air valve supplies additional air to intake manifold. Deceleration spark advance system advances ignition timing by changing vacuum supplied to valve from carburetor ported intake vacuum to intake manifold vacuum.