Abstract: A carburetor for use with internal combustion engines, wherein a jet spray of fuel is directed into the intake manifold of the engine, and the amount of fuel so sprayed under pressure is controlled by the movement of a diaphragm actuated in response to the volume of air entering the carburetor housing, so that the air-fuel mixture always will be in such proportions that all of the fuel will be burned, thereby substantially eliminating the exhaust of unused fuel to the atmosphere and the resulting air pollution, as well as increasing the engine's operating efficiency, and improving the economy.