There is disclosed a method of operating an engine assembly including a combustion engine and a common-rail injector. The method includes: injecting fuel into a combustion chamber of the combustion engine via the common-rail injector thereby generating a backflow of fuel; and powering an actuator using at least a portion of the backflow of fuel. An engine assembly including the combustion engine is disclosed; the engine assembly having a fuel circuit fluidly connecting a fuel source, the common-rail injector, and the second injector outlet together. The fuel circuit has an actuator sub-circuit operatively connected to an outlet of the common-rail injector and an actuator fluidly connected to the actuator sub-circuit.

Methods and systems are provided for operating a high pressure injection pump to provide each of high fixed fuel pressure at a port injection fuel rail and high variable fuel pressure at a direct injection fuel rail. Port injection fuel rail pressure can be raised above a pressure provided with a lift pump via a fuel system configuration that includes various check valves, pressure relief valves, and a spill valve positioned between an inlet of the high pressure injection pump and the port injection fuel rail. High pressure port injection may be advantageously used to provide fuel at high pressure during conditions when fuel delivery via high pressure direct injection is limited.

A method for operating a solenoid valve coupled to the inlet valve of a fuel injection pump comprises adjusting a pull-in electrical energy of the solenoid valve based on a fuel injection pump volumetric efficiency.

A high-pressure pump includes a pressurizing chamber forming portion, a suction passage forming portion, a seat member, a valve member, a cylindrical member, a needle, a movable core, a biasing member, a fixed core, and a coil including a winding portion. The coil generates an attractive force between the fixed core and the movable core when the winding portion is energized. The coil includes an outer cylindrical surface and multiple inner cylindrical surfaces that have different diameters. The multiple inner cylindrical surfaces are arranged in order of increasing diameter in a direction toward a pressurizing chamber. The movable core has an end surface that faces the fixed core, and the end surface of the movable core is located between a center, in an axial direction, of a smallest diameter one of the plurality of inner cylindrical surfaces and a center, in an axial direction, of the outer cylindrical surface.

A fuel delivery system for an engine is provided. The fuel delivery system includes a fuel rail, a pressure sensor, a relief valve, and a controller. The controller is configured to receive a signal indicative of a fuel rail pressure, identify exceeding of the fuel rail pressure beyond a first threshold, identify the fuel rail pressure drop below a second threshold, and initiate a counter for a first predefined amount of time accordingly. The controller is also configured to identify if the fuel rail pressure drops below a third threshold within the first predefined amount of time, and identify if the fuel rail pressure remains below the third threshold for at least a second predefined amount of time. The controller is further configured to determine an open status of the relief valve based, at least in part, on the identification.

A fuel pump includes a fuel pump housing with a pumping chamber; a pumping plunger which reciprocates within a plunger bore; and an inlet valve assembly. The inlet valve assembly includes a check valve member which is moveable between an unseated position which provides fluid communication between the pumping chamber and a fuel supply passage and a seated position which prevents fluid communication between the pumping chamber and the fuel supply passage; and a solenoid assembly which includes a wire winding; a pole piece; an armature which is moveable between a first position when the wire winding is not energized and a second position when the wire winding is energized; a return spring which biases the armature away from the pole piece; and a control rod which is moveable along the inlet valve axis independently of the armature.

A pressurized fuel injection system for an engine includes a pressure sensor in a low pressure rail, an electronic pressure regulator valve in flow communication with and downstream from the low pressure rail and in flow communication with and upstream from a fuel supply, and a controller configured to receive a pressure signal from the pressure sensor and to control the electronic pressure regulator valve in response to the pressure signal to maintain a target pressure in the low pressure rail.

A fuel pump includes a fuel pump housing with a pumping chamber; a pumping plunger which reciprocates within a plunger bore; and an inlet valve assembly. The inlet valve assembly includes a check valve member which is moveable between an unseated position which provides fluid communication between the pumping chamber and a fuel supply passage and a seated position which prevents fluid communication between the pumping chamber and the fuel supply passage; and a solenoid assembly which includes a wire winding; a pole piece; an armature which is moveable between a first position when the wire winding is not energized and a second position when the wire winding is energized; a return spring which biases the armature away from the pole piece; and a control rod which is moveable along the inlet valve axis independently of the armature.

The invention relates to a fuel-pumping device (1) for a fuel injection device of an internal combustion engine with a large high-pressure pump (16) and a small high-pressure pump (14) arranged in parallel, wherein fuel can be pumped by the large high-pressure pump (16) and by the small high-pressure pump (14) from a low-pressure region (13) into a high-pressure region (18). The high-pressure region (18) is connected to at least one injector (21). A control device (30) is provided, which can be used to conduct the entire pump output of the large high-pressure pump (16) or the small high-pressure pump (14) into the low-pressure region (13) via a discharge line (15).

A method for requirement-based servicing of an injector in a common-rail system in which, during ongoing operation of the engine, a current operating point is stored as a function of the rail pressure and of the fuel injection mass, and the current operating point is multiplied by a damage factor and is stored as a reference injection cycle as a function of the rail pressure as well as of the fuel injection mass. A total reference injection cycle is calculated by forming sums over the reference injection cycles, and a load factor is calculated as a function of the total reference injection cycle and the permissible injection cycles, and the load factor is set as decisive for the servicing recommendation of the injector.