Abstract: A high pressure fuel injection system for an internal combustion engine having a high pressure pump for delivering fuel to a fuel injector. The pressure output of the pump is sensed and is controlled to provide appropriate fuel pressure to the fuel injector for the given running condition. In addition, a release passage is formed that intersects the high pressure pump at a point intermediate the ends of its stroke and which is controlled by a control valve for releasing pressure to further provide pressure control. Even if fully opened due to failure, the release valve will not preclude the generation of pressure sufficient to run the engine.