Abstract: An internal combustion engine is operated according to a method, in which the fuel is pumped from a first fuel pump to a second fuel pump and from there into a high-pressure region. The fuel passes therefrom into at least one combustion chamber of the internal combustion engine, by means of at least one fuel injection device. In certain operating conditions of the internal combustion engine, the pressure in the high-pressure region is lowered by means of a release device. According to the invention, the reliability and security of operating the internal combustion engine may be increased by monitoring the functioning of the release device (58 through 68).

Abstract: A method for operating a fuel-supply system for an internal combustion engine of a motor vehicle is provided, the fuel-supply system having a fuel-storage tank, a fuel pump and a pressure sensor, the fuel pump supplying fuel from the fuel-storage tank to a pressure region, the pressure sensor being arranged in the pressure region, and the pressure sensor generating a signal representing the pressure in the pressure region.

Abstract: A method for operating an internal combustion engine, in particular of a motor vehicle including at least one fuel pump delivers the fuel from a fuel tank into a fuel line. The pressure of the fuel, at least in a region of the fuel line, is increased as a function of an operating state. In order to assure a reliable starting of the engine, the pressure of the fuel, at least In the above-mentioned region of the fuel line is at least intermittently increased when the engine is not running.

Abstract: In an internal combustion engine, the fuel is conveyed by an electrically driven fuel pump. The intake side of this pump is connected to a fuel tank and its outlet side is connected to a pressure region. A prerun of the electrically driven fuel pump may be performed before the startup of the internal combustion engine. In order to increase the service life of the fuel pump, an actual pressure (pactual) in the pressure region may be detected by a pressure sensor and the execution of the prerun be a function of at least the signal of the pressure sensor.

Abstract: In an internal combustion engine, the fuel reaches the combustion chamber of the engine via a fuel-injection device which includes a piezo actuator (50). In order to be able to optimally inject the fuel, it is suggested that the desired level (U_DES) of the drive energy (U) and/or the desired gradient (dU_DES) of the drive energy (U), with which the piezo actuator (50) is driven, is dependent upon a plurality of influence quantities (T, t, n, dx, dh) which influence the operating behavior of the piezo actuator (50).

Abstract: A method for detecting a hot start situation in an internal combustion of a motor vehicle includes the steps of determining a gradient of a temperature variation of an engine temperature; and detecting a hot start situation based on the determined gradient of a temperature variation of an engine temperature. An appropriate electronic control unit for an internal combustion engine is provided, as well as an appropriate computer program with a program code mechanism, and an appropriate computer program product with a program code mechanism.

Abstract: The invention is directed to a method for operating an internal combustion engine (1) wherein a fault of a pressure system with a pressure sensor (14) is determined by a first diagnostic system (14?) of the engine (1). The pressure sensor (14) is especially a pressure sensor of a high pressure fuel system of the engine. For a plausibility consideration of a pressure system fault, which is determined by the first diagnostic system (14?), at least one further diagnostic system (18?) of the engine (1) is checked as to a second fault.

Abstract: A method for operating a fuel-supply system for an internal combustion engine of a motor vehicle is provided, the fuel-supply system having a fuel-storage tank, a fuel pump and a pressure sensor, the fuel pump supplying fuel from the fuel-storage tank to a pressure region, the pressure sensor being arranged in the pressure region, and the pressure sensor generating a signal representing the pressure in the pressure region.

Abstract: A fuel delivery system for an internal combustion engine, having a fuel feed pump, which delivers fuel which is at pilot pressure to a high-pressure fuel pump that communicates on the high-pressure side with at least one injection valve, in order to deliver fuel at high pressure to the injection valve or valves. To prevent vapor bubble development in the high-pressure fuel pump, which impairs its pumping capacity and pressure generation, a coolant medium flow can be delivered to the high-pressure fuel pump via at least one coolant conduit, in order to keep the temperature (THDP) of the high-pressure fuel pump below a critical operating temperature (Tk1).

Abstract: A method for operating an internal combustion engine having a fuel pump with a drive shaft is provided, the fuel pump conveying fuel into at least one fuel-collection line, the fuel being subsequently conveyed to at least one combustion chamber via at least one fuel-injection device. In the method, a quantity of the fuel conveyed by the fuel pump into the fuel-collection line is set by means of a valve device. The valve device is configured to selectively connect a discharge side of the fuel pump to a low-pressure region of the fuel pump (during deactivation phase), and selectively disconnect the discharge side from the low-pressure region (during supply phase). In supplying the quantity of fuel, a supply rate, defined as the number of supply phases of the fuel pump per rotation of the drive shaft, is determined as a function of at least one operating parameter of the internal combustion engine.

Abstract: An internal combustion engine is operated according to a method, in which the fuel is pumped from a first fuel pump to a second fuel pump and from there into a high-pressure region. The fuel passes therefrom into at least one combustion chamber of the internal combustion engine, by means of at least one fuel injection device. In certain operating conditions of the internal combustion engine, the pressure in the high-pressure region is lowered by means of a release device. According to the invention, the reliability and security of operating the internal combustion engine may be increased by monitoring the functioning of the release device (58 through 68).

Abstract: The invention relates to a method and an arrangement for calibrating a pressure sensor (7) of a fuel-metering system of an internal combustion engine wherein the fuel-metering system includes: a high-pressure pump (2) for pumping fuel from a low-pressure region (ND) into a high-pressure region (HD) injectors (5) for metering the fuel from the high-pressure region (HD) into combustion chambers (6) of the internal combustion engine with the injectors (5) being drivable in dependence upon operating characteristic variables, and the pressure sensor (7) for measuring the pressure in the high-pressure region (HD).

Abstract: The fuel supply apparatus for supplying fuel to an internal combustion engine has a fuel tank (2), a first fuel pump (6) that supplies fuel from the fuel tank to a fuel line (10), a second fuel pump (12) that supplies fuel from the fuel line (10) via a pressurized line to at least one fuel valve (16) and a fuel return line (22) that connects the fuel line (10) to the fuel tank for return of excess fuel. A shut off valve (30), which is closed at high temperatures, and a pressure regulator valve (26) are arranged hydraulically in series in the fuel return line (22). A fuel scavenger line (60) is provided, by which fuel at high temperatures is returned to the fuel tank (2). The fuel scavenger line (60) conducts the fuel back to the fuel tank (2), at least partially through the second fuel pump (12) and through a hydraulic resistance. Gas bubble formation is prevented by a high fuel supply pressure and by transfer of heat from the second fuel pump (12).

Abstract: An injection system for internal combustion engines is proposed, in which once the engine has been turned off, a pressure equalization is established between the intake side and the pressure side of the high-pressure fuel pump. This prevents uncombusted fuel from reaching the combustion chambers of the engine. The pressure prevailing on the pressure side and the intake side when the engine is off furthermore assures that vapor bubbles cannot form, and this makes starting the engine easier.

Abstract: A fuel system serves to supply fuel to an internal combustion engine includes a reservoir and a first fuel pump whose input is connected to the reservoir and a second fuel pump whose input is connected to the first fuel pump. At least one injection valve is connected to the second fuel pump and can supply fuel at least indirectly to a combustion chamber. A leakage line is provided between the second fuel pump and the reservoir. In order to permit a reliable hot start of the engine with a simultaneously low strain on the components, the leakage line is provided with a valve device which has a shutoff function and a pressure relief function that are connected in parallel with each other.

Abstract: A method for operating an internal combustion engine, e.g., of a motor vehicle, where fuel is supplied under pressure via at least one injection valve. The injected fuel quantity is influenced by the injection time of injection valve. In order to be able to provide optimum operating comfort and good component reliability even in the event of an incorrect fuel pressure, a maximum allowable torque of the internal combustion engine that is dependent on the instantaneous fuel pressure is determined.

Abstract: In an internal combustion engine, the fuel is conveyed by an electrically driven fuel pump. The intake side of this pump is connected to a fuel tank and its outlet side is connected to a pressure region. A prerun of the electrically driven fuel pump may be performed before the startup of the internal combustion engine. In order to increase the service life of the fuel pump, an actual pressure (pactual) in the pressure region may be detected by a pressure sensor and the execution of the prerun be a function of at least the signal of the pressure sensor.

Abstract: Method for varying a prepressure (p_des) generated by a low-pressure pump and applied to a high-pressure pump with the low-pressure pump (2) and the high-pressure pump (3) pumping fuel for the internal combustion engine (1). In order to keep the prepressure (p_des), on the one hand, as low as possible to take load off the low-pressure pump (2) and to, on the other hand, adjust the prepressure (p_des) so high that a vaporization of the fuel is reliably avoided, the invention suggests that: the actual temperature (T_Krst) of the fuel in the high-pressure pump (3) is determined; a prepressure (p_des) as low as possible is determined in dependence upon the fuel temperature (T_Krst) for which a vaporization of the fuel in the high-pressure pump (3) is reliably avoided; and, the low-pressure pump (2) is so driven or controlled that it generates the determined prepressure (p_des). The method is preferably carried out on the basis of physical models of the high-pressure pump (3).

Abstract: The invention concerns a method for detecting a hot start situation in an internal combustion engine of a motor vehicle. The invention also concerns an appropriate electronic control unit for an internal combustion engine, an appropriate computer program with program code means, and an appropriate computer program product with program code means.

Abstract: The invention relates to a method for reducing the fuel pressure in a return-free fuel supply system of an internal combustion engine to a desired pressure value. At least one fuel pump is mounted in the fuel supply system. In order to be able to reduce the fuel pressure in the fuel supply system in a simple manner without additional pressure release valves, the suggestion is made that the fuel supply system and the internal combustion engine be operated in a pressure-reduction mode wherein at least one fuel pump of the fuel supply system is so controlled (open loop and/or closed loop) that the desired pressure value is adjusted in the fuel supply system. The fuel supply system is preferably configured as a common-rail storage injection system for a direct-injecting internal combustion engine.