Fuel injection system

The IC engine has the fuel supplied to the common-rail fuel injection system via an unregulated high pressure pump with a control device (24) inserted in the fuel feed line. The high pressure pump has a single pump element (10) within a pump housing incorporated in the crank housing of the engine, with an operating rod having a roller cooperating with an injection cam of a valve camshaft (4) and coupled to a pump plunger.