Deceleration enrichener system

In an internal combustion engine having a fuel/air delivery system supplying a fuel/air mixture for combustion by said engine, said delivery system having an idle air inlet port, a deceleration enrichener system including a valve operated by engine manifold vacuum and closing said idle air inlet port upon deceleration of said engine to enrich the fuel/air ratio of said mixture.

• wherein said valve comprises:
• a valve body with an internal chamber;
• a first port communicating with said idle air inlet port;
• a second port providing an air inlet port;
• a third port communicating with said engine manifold vacuum;
• a valve seat between said first and second ports;
• a movable plunger responsive to a first level of engine manifold vacuum to move to an open position disengaging said valve seat and enabling communication between said first and second ports, and responsive to a second higher level of engine manifold vacuum upon deceleration of said engine to move to a closed position engaging said valve seat and blocking communication between said first and second ports;
• a diaphragm separating said chamber into first and second compartments on opposite sides of said diaphragm and isolated and sealed from each other by said diaphragm;
• a subcompartment communicating through said valve seat with said first compartment;
• said first port communicating with said subcompartment;
• said second port communicating with said first compartment;
• said third port communicating with said second compartment.