METHOD OF CORRECTING A STANDARD CHARACTERISTIC CURVE OF A STANDARD FUEL INJECTOR OF AN INTERNAL COMBUSTION ENGINE

A method and control apparatus configured to correct a standard characteristic curve of a standard fuel injector of an internal combustion engine. First and second injected fuel quantity corresponding to an energizing time which is higher than a reference energizing time are determined from the standard characteristic curve. A standard fuel quantity increment is calculated as the difference between the second and first injected fuel quantities associated to the reference energizing time. First and second injected fuel quantity corresponding to an energizing time which is higher than the energizing time by the time interval are determined from a master characteristic curve for each of the energizing times and a master fuel quantity increment is calculated as the difference between the second and the first injected fuel quantities associated to the energizing time, a difference between the master fuel quantity increment and the standard fuel quantity increment, and a value of a predetermined parameter as a function of the difference. The energizing time for which the value of the parameter is a minimum is identified and an energizing time correction value is calculated as a difference between the reference energizing time and the identified energizing time, The energizing time correction value is used to correct the standard characteristic curve.