US Patent 9291110 Control device for internal combustion engine

When an alcohol mixed fuel is supplied to an internal combustion engine, the magnitude of the alcohol concentration is determined, and the magnitude of an operation state temperature is determined on the basis of the determination. When the alcohol concentration is high and the operation state temperature is low, the generation of intermediate products, which are alcohol oxides contained in unburned alcohol mixed fuel, is promoted, and the intermediate products generated are trapped in an intake passage by opening an intake valve in the expansion stroke of the internal combustion engine.