Abstract: Upstream of the electrically operated fuel injectors for each engine cylinder there is connected a common pressure reservoir subject via a valve to the action of a continuously delivering fuel pump as a function of the engine speed and load. The common pressure reservoir is continuously connected by means of an annular chamber and a throttle to a channel in each fuel injector. Each fuel injector has a solenoid or magnetic valve operable for each fuel injection process and during the operation thereof connects said channel with a fuel return pipe and consequently relieves or releases the nozzle needle closing the fuel injection opening, thus releasing the discharge of fuel from a pressure chamber located directly upstream of the fuel injection opening. The channel is continuously connected via a throttle bore bridging a check valve to a control chamber controlling the nozzle needle movement.