A method of controlling an amount of fuel to be injected by a fuel injector into a cylinder of an internal combustion engine is disclosed. A map stores values of a fuel injection quantity drift of said injector. A fuel injection quantity drift is estimated and stored in a corresponding map point to a current engine operating point. A set of map points whose distance from said corresponding map point is smaller than a given distance are selected. All map points of the set of map points are modified by multiplying their entries by a radial weighing factor. The amount of fuel to be injected by the fuel injector to be the requested amount of fuel is corrected by means of the corresponding entry of the map.