Disclosed is a method and a device for predicting the failure time of the pressure limiting valve of a high-pressure fuel pump of a motor vehicle. The method includes measuring a characteristic parameter of the pressure limiting valve each time the motor vehicle has been switched off, determining and storing a variable determined by using the measured characteristic parameter, determining the time profile of the variable determined from the characteristic parameter, predicting the future profile of the variable determined from the characteristic parameter, and comparing the predicted future profile of the variable determined from the characteristic parameter with a predetermined wear limiting value. The comparison is to predict the time at which the predicted future profile of the variable determined from the characteristic parameter reaches the predetermined wear limiting value.

Embodiments relate to an operating method for operating a fuel injection system of an internal combustion engine, wherein, upon a detection of a fault in the fuel injection system, and wherein a predefined pressure is overshot in a high-pressure region of the fuel injection system, an overrun mode of the internal combustion engine is deactivated, such that the internal combustion engine is operated exclusively in an injection mode.

The disclosure relates to a fuel injection system having a valve arrangement for connecting a pressure chamber of a high-pressure fuel pump to a high-pressure accumulator. The valve arrangement has an outlet valve and a pressure-limiting valve. An outlet valve seat and a pressure-limiting valve seat are formed on a common valve seat element which is formed in one piece, and are arranged eccentrically with respect to one another.

The disclosed inlet check valve is used in a high pressure fuel pump and is comprised of a valve member integrally connected to a valve stem which is coupled to an inlet valve armature. The valve member has a stroke along an axis between an open position and a closed position. An inlet valve solenoid generates a magnetic field in an inlet valve pole to attract the inlet valve armature and move the valve member from the open position to the closed position. In the open position, the valve member contacts an inlet valve stop and a gap greater than the stroke of the valve member is defined along the axis between the inlet valve armature and the inlet valve pole. In the closed position, an inlet valve seat mates with the valve member and an armature gap remains between the inlet valve armature and the inlet valve pole.

The disclosed integrated outlet check valve and pressure relief valve are used in a high pressure fuel pump including a pumping chamber and an outlet fitting defining an outlet passage to a common rail. The pressure relief valve comprises a movable pressure relief valve shuttle including a pressure relief valve surface configured to mate with a pressure relief valve seat in a closed position. The pressure relief valve shuttle moves from the closed position to an open position when pressure in the common rail exerts a force greater than the bias of a pressure relief valve spring. The pressure relief valve shuttle also includes an outlet check valve seat configured to mate with an outlet check valve ball in a closed position. The outlet valve ball moves from the closed position to an open position when pressure in the outlet passage is less than pressure in the pumping chamber.

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).

The disclosure relates to a control method for controlling at least one injector valve in a fuel injection system of an internal combustion engine. An opening time of the injector valve is selected such that, in a fault situation in the fuel injection system, an opening time of the injector valve is situated in a pressure valley of a pressure oscillation prevailing in a high-pressure region of the fuel injection system.

An outlet valve includes an outlet valve housing with an outlet valve bore including an outlet valve seating surface. The outlet valve also includes an outlet valve member which moves within the outlet valve bore second portion between a closed position and an open position. A surface of the outlet valve bore guides the outlet valve member during movement between the closed position and the open position. The surface of the outlet valve bore and the outlet valve seating surface are provided on a continuous piece of material of the outlet valve housing. An outlet valve spring biases the outlet valve member toward the closed position and a retainer is fixed to the outlet valve housing which grounds the outlet valve spring to the outlet valve housing.

Methods and systems are provided for adjusting operation of fuel injectors of an internal combustion engine to reduce injector ticking noise during direct injection fuel rail pressure release. The method includes first reducing a significant part of the direct injection fuel rail pressure via a mechanical high pressure pump relief valve and only if further pressure relief is required then intermittently activating the direct injector to inject in small amount of fuel. Due to the reduced frequency of activation and small pulse-widths, the impact force transmitted from injectors to cylinder head is small thereby reducing the objectionable ticking noise.

A control device is applied for an internal combustion engine which is provided with a high-pressure fuel pump driven by a driving shaft of the internal combustion engine to discharge a fuel pressurized in a pressurizing chamber, an accumulator accumulating a high-pressure fuel discharged from the high-pressure fuel pump, and a relief valve which is opened when a fuel pressure in the accumulator is higher than a specified pressure in order to return the fuel in the accumulator to a specified chamber where a fuel has lower pressure than a fuel in the pressurizing chamber. An idle speed of the internal combustion engine is increased to a specified speed when the fuel pressure in the accumulator has been higher than a determination pressure, which is lower than the specified pressure, for a first period or longer.