Fuel injection system for an internal combustion engine

In a fuel injection system for an internal combustion engine, having one high-pressure fuel pump and one fuel injection valve, communicating with the high pressure pump for each cylinder of the engine, in which the high-pressure fuel pump has a pump piston driven at least indirectly by the engine in a reciprocating motion and defining a pump work chamber, and the fuel injection valve has at least one injection valve member by which at least one injection opening is controlled and which is urged in an opening direction by the pressure prevailing in a pressure chamber of the fuel injection valve communicating with the pump work chamber and is movable counter to a closing force in the opening direction for uncovering the at least one injection opening, having an electrically actuated control valve, by which a communication of the pump work chamber with a relief region is controlled at least indirectly, and a movable control piston which acts at least indirectly on the at least one injection valve member in the closing direction, and the control piston, on its side remote from the at least one injection valve member, being acted upon at least indirectly by the pressure prevailing in the pump work chamber, the improvement wherein the control piston, with its side toward the at least one injection valve member, defines a control chamber;

• wherein the communication, controlled by the control valve, discharges toward the relief region;
• and wherein the control chamber communicates at least indirectly with the pump work chamber via a throttled communication.