Closed Loop Carburetor Emission Control System

Electronic control logic and system components are described that are used with a venturi carburetor to accomplish the fuel metering required in a closed loop emission control system. Special open loop functions are used because of the nature of the venturi carburetor and the warm-up characteristics of the three-way catalytic converter and exhaust gas sensors. Strip chart recordings illustrate the dynamic characteristics of the electronic control logic, and emission test results with a low mileage three-way converter are set forth.