A system and method for regulating the pressure within a volume between a pressure regulator and an injector that injects hydrogen gas into the anode side of a fuel cell stack. The method includes delaying a copy of the a pulsed signal that controls the opening and closing of the injector a predetermined period of time and provides a bias signal from a look-up table that is determined by a desired average mass flow of the hydrogen gas flow to the fuel cell stack and the pressure at an upstream location of the hydrogen gas flow from the pressure regulator. The method selects the bias signal as a pressure regulator control signal that controls the pressure regulator when the delayed pulse injector signal is high and selects an arbitrary value at or near zero as the pressure regulator control signal when a delayed pulse injector is low.