Patent ID: 7607422

Claim:
An apparatus converting an OEM type engine having an OEM type of fuel system and exhaust system using an OEM type recommended fuel fed to the engine from an OEM type fuel tank, the apparatus comprising: varying proportions of an alternate fuel being mixed with the OEM recommended fuel in the OEM type fuel tank to form a varying fuel mixture; a sensor added to detect the proportional amount of alternative fuel in the fuel mixture being fed to the OEM fuel system from the OEM fuel tank, the sensor being selected from a group consisting of: a) an exhaust gas O 2 sensor; and b) a fuel composition sensor; a fuel injector driver circuit added to the OEM type engine to control an output signal to a fuel injector; an electronic control unit added to the OEM type engine to control the fuel injector driver circuit, the electronic control unit being arranged to receive an input signal from the sensor; and the electronic control unit being arranged to change the output signal from the fuel injector driver circuit to the fuel injector to vary the amount of the fuel being metered into the OEM type engine to control the engine's operating condition to maintain a correct air-to-fuel ratio needed for proper combustion of the fuel mixture fed from the OEM fuel tank.