with no fuel pressure being sensed, the injector stays open longer through PWM. The injector if not operating correctly will cause the unit to try and compensate PWM to injector. Remember all you are seeing is the electrical pulse when looking @ injector pulse on dash. It doesn't know the if the injector is super glued shut or open...its just a pulse listed in microseconds. In other words it is telling the injector to open but the injector may not be on the same page with the ecm