Abstract: A fuel-air injection control system is provided for internal combustion engines using gasoline as a fuel. The system includes a vacuum pump which is connected to an airtight fuel supply tank containing a liquid gasoline such that operation of the vacuum pump causes a portion of the liquid gasoline to be continuously vaporized. The vaporized but unheated gasoline is passed through a filter where unwanted contaminants are removed and is delivered to the intake ducts of the internal combustion engine. Heated air is also supplied to these intake ducts and the vaporized gasoline combines with heated combustion air therein for subsequent ignition in the combustion chambers. The flow of heated combustion air is controlled by the operator to control the speed of the engine.