METHOD FOR DETERMINING THE ALCOHOL CONTENT OF A NEW FUEL MIXTURE IN AN INTERNAL COMBUSTION ENGINE OF A VEHICLE, AND DEVICE FOR IMPLEMENTING SAID METHOD

摘要

A method for determining the alcohol content of a fuel mixture for a vehicle internal combustion engine that can be sequentially supplied with two types of fuel having a predetermined composition, at least one of which contains a mixture of gasoline and alcohol, includes, after feeding an amount of new fuel into the vehicle tank previously containing an amount of old fuel mixture, determining the first moment at which the new fuel mixture is supplied to the first injector. After the first moment, and from the first sufficiently long period during which the operating state of the engine is stabilized, determining an optional variation trend of the richness of the air/fuel mixture relative to a previously measured richness, deducing the type of new fuel supplied and, by cross-checking this information with the respective volumes of old and new fuels in the tank, determining the alcohol content of the new mixture.