Fuel ethanol content determining method for internal combustion engine of motor vehicle i.e. flexible fuel vehicle, involves determining ethanol content of fuel depending on determined loading degree of activated carbon filter

摘要

The method involves determining a loading degree of an activated carbon filter (64) for filtering hydrocarbon vaporized in a fuel (52) in a fuel tank (50). Ethanol content of the fuel is determined depending on the determined loading degree of the activated carbon filter. A petrol content of the fuel is determined depending on the loading degree of the carbon filter. The ethanol content of the fuel is determined depending on the determined petrol content. The carbon filter is rinsed with fresh air. A combustion process of the internal combustion engine is executed with fresh air. An independent claim is also included for a device for determining ethanol content of fuel in a fuel tank of an internal combustion engine.