A direct injection (DI) fuel supply system includes an accumulator valve coupled to a high pressure fuel line at a position between an accumulator and a fuel rail. A controller of the DI fuel supply system is configured to control the accumulator valve to maintain the pressurized fuel housed in the fuel rail at a desired pressure and to control the accumulator valve proximate a fuel injection event by a fuel injector such that the accumulator supplies the fuel rail with approximately the portion of the pressurized fuel injected by the fuel injector during the fuel injection event. This positioning of the accumulator valve between the DI positive displacement fuel pump and the fuel rail together with active control thereof also insulates the fuel rail and the fuel injector from fuel pressure pulsations generated by the DI positive displacement fuel pump.