Closed-loop method for operating a direct injection fuel system

The invention provides a inethod for operating a direct injection system of an internal combustion engine of a motor vehicle, wherein at least one fuel injection patameter, for example the timing of a pilot injection, main injection or the dwell time between the two injections, is adjusted by a closed loop control of the injected fuel quantity. The method may relate to the control of solenoid injectors and may provide a multi-injection pattern having at least two consecutive injection events separated by less than 100 micro seconds. The control system provides fine adjustment of injection control such that the flow rate of fuel can be ramped from one value to another.