Abstract

In a method of controlling the operation of an internal combustion engine with fuel injection by way of a common high pressure (common rail) fuel supply line to which high pressure fuel is supplied by a high pressure fuel pump and from which fuel is admitted to the various cylinders of the internal combustion engine by valve controlled fuel injection nozzles, the fuel pressure in the common fuel supply line between the end of an injection and the start of a fuel supply period is monitored at distinct timely spaced measurement points and, if a pressure difference between the measurement points is sensed in excess of a predetermined limit value indicating an injector malfunction, the high pressure fuel supply to the common fuel supply line is interrupted by deactivating the high pressure fuel pump while fuel injection through the operative nozzles is maintained so as to rapidly reduce the pressure in the common fuel supply line.