Abstract: A method for ascertaining a variable characterizing a flow rate of a fuel injector during an operation of an internal combustion engine, to which the fuel injector is assigned. At least two input values for a data-based model are ascertained, and at least one output value is determined with the aid of the data-based model, on the basis of which a value for the variable characterizing the flow rate of the fuel injector is ascertained. The data-based model combines at least two methods differing from one another for ascertaining a variable characterizing a flow rate of a fuel injector.

Abstract: A method for ascertaining a variable characterizing a flow rate of a fuel injector during an operation of an internal combustion engine, to which the fuel injector is assigned. At least two input values for a data-based model are ascertained, and at least one output value is determined with the aid of the data-based model, on the basis of which a value for the variable characterizing the flow rate of the fuel injector is ascertained. The data-based model combines at least two methods differing from one another for ascertaining a variable characterizing a flow rate of a fuel injector.

Abstract: A method for determining an average segment time of an encoder wheel of an internal combustion engine, the encoder wheel being connected in rotationally fixed fashion to a crankshaft of the internal combustion engine, markings being situated along the circumference of the encoder wheel, and the crankshaft of the internal combustion engine passing through specified angular ranges during segment times, segment times being acquired, associated rotational speed values being determined from the segment times, a rotational speed curve being determined from the individual determined rotational speed values, a value of the average rotational speed being determined from the rotational speed curve, and an average segment time being determined from the value of the average rotational speed.

Abstract: In the method provided herein, quantities of fuel are determined during a direct injection of a motor vehicle. In this connection, within one work cycle, test injections are carried out in two cylinders of an internal combustion engine of the motor vehicle during overrun phases, speed oscillations of moved masses of the cylinders are measured and a relative difference in quantity of the fuel quantity of the test injections within one work cycle is determined from the speed oscillations. By evaluating a relative signal between the test injections within one work cycle in the two cylinders, an intrinsic dependence of the drive train of the quantity of fuel signal is compensated.

Abstract: A method for determining an average segment time of an encoder wheel of an internal combustion engine, the encoder wheel being connected in rotationally fixed fashion to a crankshaft of the internal combustion engine, markings being situated along the circumference of the encoder wheel, and the crankshaft of the internal combustion engine passing through specified angular ranges during segment times, segment times being acquired, associated rotational speed values being determined from the segment times, a rotational speed curve being determined from the individual determined rotational speed values, a value of the average rotational speed being determined from the rotational speed curve, and an average segment time being determined from the value of the average rotational speed.

Abstract: A method is provided for ascertaining the fuel quality in an internal combustion engine, in particular of a motor vehicle, in which it is provided, in particular, that a two-stage zero quantity calibration is carried out, in which, in the first stage, a test injection is carried out with a control duration and a first quantity correction is generated, and, in the second stage, two test injections are carried out with the mentioned control duration, whose time interval is selected in such a way that the influence of a pressure wave which is generated by the first test injection on the second test injection is preferably low, and a second quantity correction is generated on the basis of the two test injections, and the first quantity correction and the second quantity correction are compared with one another and the fuel quality is inferred from the result of the comparison.

Abstract: In a method for calibrating a fuel metering system including an injector of an internal combustion engine performing a pilot injection chronologically prior to a main injection, at least two test injections chronologically prior to the pilot injection are provided for the injector, the first test injection being carried out using a first activation duration, in which the injector does not yet open, at least one second test injection being carried out in a subsequent injection cycle using an activation duration which is progressively increased in each case in relation to the first test injection until a change of an operating variable of the fuel metering system or the internal combustion engine results, which activation duration corresponds to a minimum activation duration of the injector.

Abstract: In the method provided herein, quantities of fuel are determined during a direct injection of a motor vehicle. In this connection, within one work cycle, test injections are carried out in two cylinders of an internal combustion engine of the motor vehicle during overrun phases, speed oscillations of moved masses of the cylinders are measured and a relative difference in quantity of the fuel quantity of the test injections within one work cycle is determined from the speed oscillations. By evaluating a relative signal between the test injections within one work cycle in the two cylinders, an intrinsic dependence of the drive train of the quantity of fuel signal is compensated.

Abstract: A method for controlling an internal combustion engine includes: using the pressure sensor method, determining for a first injector a first control period during which a desired quantity of fuel is injected into a lead cylinder; controlling the first injector with the first control period and entering a quantity replacement signal resulting therefrom into a training characteristic field as a function of the drive train parameters; and using null quantity calibration, varying for all further cylinders a control period of the injectors assigned to the cylinders until the quantity replacement signal is reached.

Abstract: In a method for calibrating a fuel metering system including an injector of an internal combustion engine performing a pilot injection chronologically prior to a main injection, at least two test injections chronologically prior to the pilot injection are provided for the injector, the first test injection being carried out using a first activation duration, in which the injector does not yet open, at least one second test injection being carried out in a subsequent injection cycle using an activation duration which is progressively increased in each case in relation to the first test injection until a change of an operating variable of the fuel metering system or the internal combustion engine results, which activation duration corresponds to a minimum activation duration of the injector.

Abstract: A method and a device for controlling an injection system of an internal combustion engine are described, in which at least two consecutive partial injections are compensated for using pressure wave compensation, it is provided in particular that two test injections having a specified time interval to one another are triggered in a cylinder of the internal combustion engine, the total injection quantity of the at least two partial injections is ascertained, and a deviation between the ascertained total injection quantity and an expected total injection quantity is assumed as the error of the pressure wave compensation and a correction value for the pressure wave compensation is determined therefrom.