Abstract: The present application relates to a fuel injection system of an internal combustion engine having an automatic stop-start system, the fuel injection system comprising a high pressure fuel pump, which via a fuel pump line delivers fuel towards a common fuel rail, to which a fuel return line is connected. It is proposed that the fuel return line comprise a control element system, which firstly discharges a fuel pressure to a fuel tank, when a first predefined pressure limit is reached in the fuel return line, and which secondly prevents a further flow of fuel from the return line into the fuel tank, but allows a flow of fuel from the fuel tank into the fuel return line, so that the return line is designed as a fuel pressure accumulator.