Fuel injection system of a combustion engine and method for controlling same

The method involves compressing low pressure volume to high pressure, where the low pressure volume is supplied from a low pressure region (1). The low pressure volume is conveyed into a pressure reservoir (11) of a high pressure region (2) by a high pressure fuel pump (3). The low pressure volume of the high pressure fuel pump is dosed corresponding to injection pressure to be reached in an operating point of a combustion engine. The low pressure amount is adjusted by controlling a delivery rate of a feed pump (5) and a throttle amount of a dosing unit (8). An independent claim is also included for a fuel injection system of a combustion engine comprising a high pressure fuel pump.