Deceleration Mixture Control System

This system is designed to allow fresh air into the intake manifold to reduce excessive HC and CO emission caused by temporary rich air/fuel ratio during rapid deceleration. This system consists of an MCV, jet and vacuum hoses. The MCV consists of a pressure balancing orifice and a check valve on its diaphragm, and closes when manifold vacuum is constant. When manifold vacuum becomes constant, pressure difference between chambers A and B, gradually diminishes through the pressure balancing orifice, then the MCV.