Abstract: A method for operating a common-rail system of a motor vehicle that includes a common-rail-pressure sensor configuration having at least two signal paths, and that can be operated at a maximally permissible common-rail pressure and at a minimally permissible common-rail pressure. Sensor signals are read out in each case in response to a pressure measurement in a common rail of the common-rail system via the at least two signal paths, and a signal deviation value is ascertained that characterizes a deviation between the pressure values that are each determined on the basis of the sensor signals. The method includes reducing the maximally permissible common-rail pressure by a correction value to a maximally permissible emergency common-rail pressure and/or increasing the minimally permissible common-rail pressure by a correction value to a minimally permissible emergency common-rail pressure in response to the signal deviation value exceeding a predefined value.

Abstract: A method for determining a value of a current, which is required for changing a switching state of a pressure control valve of a fuel delivery system, in which the current flowing through the pressure control valve is varied from a starting value up to a target value, and a time curve of the current is analyzed, the value required for changing the switching state being reached when the curve of the current has a change in slope, this change being detected via a first derivation over time of the current.

Abstract: The invention proposes a fuel delivery device for a fuel injection device of an internal combustion engine, having a delivery pump (10) and having at least one high-pressure pump (16). By means of the delivery pump (10), fuel from a storage container (12) is delivered to the suction side of the high-pressure pump (16), and fuel is delivered into a high-pressure region (18) by the high-pressure pump (16). The delivery pump (10) has an adjustable displacement volume, which means that a variable quantity of fuel can be conveyed at the same rotational speed.

Abstract: A method for operating a common-rail system of a motor vehicle that includes a common-rail-pressure sensor configuration having at least two signal paths, and that can be operated at a maximally permissible common-rail pressure and at a minimally permissible common-rail pressure. Sensor signals are read out in each case in response to a pressure measurement in a common rail of the common-rail system via the at least two signal paths, and a signal deviation value is ascertained that characterizes a deviation between the pressure values that are each determined on the basis of the sensor signals. The method includes reducing the maximally permissible common-rail pressure by a correction value to a maximally permissible emergency common-rail pressure and/or increasing the minimally permissible common-rail pressure by a correction value to a minimally permissible emergency common-rail pressure in response to the signal deviation value exceeding a predefined value.

Abstract: A method for operating a pressure-regulating valve of a fuel injection system of an internal combustion engine of, in particular, a motor vehicle; the fuel injection system including a pressure reservoir for storing pressurized fuel, as well as a feed device for delivering fuel to the pressure reservoir; and fuel being removable from the pressure reservoir via the pressure-regulating valve. In an overrun mode of the internal combustion engine, a delivery quantity of fuel delivered to the pressure reservoir by the feed device is set to a value greater than zero, and that a fuel pressure in the pressure reservoir is ascertained.

Abstract: A method for determining a value of a current, which is required for changing a switching state of a pressure control valve of a fuel delivery system, in which the current flowing through the pressure control valve is varied from a starting value up to a target value, and a time curve of the current is analyzed, the value required for changing the switching state being reached when the curve of the current has a change in slope, this change being detected via a first derivation over time of the current.

Abstract: A method is described for operating a fuel injection system, in particular of an internal combustion engine, in which fuel under pressure is made available in a pressure reservoir and a fuel pressure prevailing in the pressure reservoir is ascertainable with the aid of a pressure sensor. Fuel is removed from the pressure reservoir over a predefinable pressure reduction time period, measured pressure values are ascertained (determined) with the aid of the pressure sensor at least two different points in time during the pressure reduction period, and an actual fuel pressure at the beginning of the pressure reduction period is inferred from the measured pressure values ascertained (determined) during the pressure reduction period.

Abstract: A method for ascertaining an error in a fuel metering unit of an injection system for an internal combustion engine, wherein the gradients of a first signal representing a physical variable and of a second signal representing a physical variable are determined, and at a predefined magnitude and/or direction of the two gradients an error is recognized.

Abstract: A method for operating a pressure-regulating valve of a fuel injection system of an internal combustion engine of, in particular, a motor vehicle; the fuel injection system including a pressure reservoir for storing pressurized fuel, as well as a feed device for delivering fuel to the pressure reservoir; and fuel being removable from the pressure reservoir via the pressure-regulating valve. In an overrun mode of the internal combustion engine, a delivery quantity of fuel delivered to the pressure reservoir by the feed device is set to a value greater than zero, and that a fuel pressure in the pressure reservoir is ascertained.

Abstract: The invention proposes a fuel delivery device for a fuel injection device of an internal combustion engine, having a delivery pump (10) and having at least one high-pressure pump (16). By means of the delivery pump (10), fuel from a storage container (12) is delivered to the suction side of the high-pressure pump (16), and fuel is delivered into a high-pressure region (18) by the high-pressure pump (16). The delivery pump (10) has an adjustable displacement volume, which means that a variable quantity of fuel can be conveyed at the same rotational speed.

Abstract: A method for determining a fuel mass of a single injection that has been injected into at least one combustion chamber of a combustion engine with at least one injection under high pressure. The method includes determining a correction variable for the single injection with the aid of a comparison of a measure for the actual amount of the injected fuel of at least one test injection, which takes place due to a measure for a default nominal amount of a desired single injection, and a measure for the nominal amount of the test injection. The method additionally includes executing a plurality of timely directly successive test injections.

Abstract: A method and a device for controlling a fuel metering system are described. The fuel metering system includes at least one injector for injecting fuel into an internal combustion engine. An electric current value is applied to the at least one injector, and a rail pressure value is determined based on the electric current value.

Abstract: A method is described for operating a fuel injection system, in particular of an internal combustion engine, in which fuel under pressure is made available in a pressure reservoir and a fuel pressure prevailing in the pressure reservoir is ascertainable with the aid of a pressure sensor. Fuel is removed from the pressure reservoir over a predefinable pressure reduction time period, measured pressure values are ascertained (determined) with the aid of the pressure sensor at least two different points in time during the pressure reduction period, and an actual fuel pressure at the beginning of the pressure reduction period is inferred from the measured pressure values ascertained (determined) during the pressure reduction period.

Abstract: A method and a device for controlling a fuel metering system are described. The fuel metering system includes at least one injector for injecting fuel into an internal combustion engine. An electric current value is applied to the at least one injector, and a rail pressure value is determined based on the electric current value.

Abstract: A method for ascertaining an error in a fuel metering unit of an injection system for an internal combustion engine, wherein the gradients of a first signal representing a physical variable and of a second signal representing a physical variable are determined, and at a predefined magnitude and/or direction of the two gradients an error is recognized.

Abstract: A method for determining a fuel mass of a single injection that has been injected into at least one combustion chamber of a combustion engine with at least one injection under high pressure. The method includes determining a correction variable for the single injection with the aid of a comparison of a measure for the actual amount of the injected fuel of at least one test injection, which takes place due to a measure for a default nominal amount of a desired single injection, and a measure for the nominal amount of the test injection. The method additionally includes executing a plurality of timely directly successive test injections.

Abstract: A method for operating a fuel-injection system, in particular of an internal combustion engine, in which fuel stored inside a pressure reservoir is injected by at least one fuel injector. At least one performance quantity of the fuel injector that is a function of the fuel pressure prevailing inside the pressure reservoir is evaluated in order to infer the fuel pressure.