Abstract: The invention relates to a method for regulating a fuel tank venting valve of a motor vehicle during leak testing of a fuel tank venting system where the fuel tank venting valve is arranged in a recovery line that connects a retention vessel to catch fuel vapors from a fuel tank to an inlet manifold of an operating internal combustion engine, comprising sealing the tank venting system from the atmosphere outside the motor vehicle, opening the fuel tank venting valve to expose the fuel tank and the tank venting system to a relative negative pressure present in the inlet manifold of the operating internal combustion engine and regulating the degree of opening of the tank venting valve based upon the external pressure, pA.

Abstract: In a method for diagnosing an injection valve (5), in an overrun fuel cut-off phase the fuel supply to the fuel rail (4) is closed, and after the fuel supply has been closed off a first fuel pressure in the fuel rail (4) is measured, and after the first measurement of the fuel pressure an injection valve (5) is actuated for a test injection. After the test injection a second fuel pressure in the fuel rail (4) is measured, a differential pressure value (?P) is formed from the first and second measured fuel pressures and a difference of an operating parameter from a reference parameter is determined from the differential pressure value (?P), and when a previously defined maximum difference is exceeded the injection valve (5) is detected as being defective.

Abstract: A regulating method and a regulating device for actuating an actuator in an injection system for an internal combustion engine, may have the following steps: stipulation of a setpoint value for a controlled variable of the actuator; determination of an actual value of the controlled variable; determination of a setpoint/actual value deviation between the setpoint value and the actual value of the controlled variable; pilot control of a controlled variable in accordance with a predefined pilot control response as a function of the setpoint value; regulation of the controlled variable by a regulator output variable in accordance with a predefined regulating response as a function of the feedback setpoint/actual value deviation; actuation of the actuator with the pilot-controlled and regulated controlled variable; and determination of a characteristic variable of the injection system as a function of the regulator output variable.

Abstract: In known methods for carrying out a high-pressure start of an internal combustion engine, inconvenient starting behavior can sometimes occur. In a method for carrying out a high-pressure start of an internal combustion engine (1), a high-pressure pump (22) is used to feed fuel from a fuel tank (17) to a pressure accumulator (20) and a pressure adjuster (23) is used to control the pressure in the pressure accumulator (20), wherein the high-pressure pump (22) is operated before carrying out a fuel injection into a combustion chamber of the internal combustion engine (1), and the pressure adjuster (23) is activated in such a way that, during the operation of the high-pressure pump (22), the pressure build-up in the pressure accumulator (20) above a pressure limit value pTHRES, upon the exceedance of which the fuel injection is enabled, is delayed.

Abstract: In a regulating method for controlling an electrical actuator, especially a valve for regulating a volume flow in an injection system for an internal combustion engine, a nominal value is set for an actuating variable of the actuator; the actuator is controlled by a pulse width-modulated electrical control signal with a pre-defined pulse duty factor and a pre-defined period for adjusting the desired nominal value of the actuating variable; a flow threshold value is determined according to the pre-defined nominal value for the actuating variable; the flow flowing through the actuator is continuously measured during the control by the control signal and before the end of the period; the measured flow is compared with the flow threshold value/and the flow flowing through the actuator is switched off before the end of the period of the control signal if the measured flow exceeds the current threshold value.

Abstract: In a control method for an internal combustion engine (1) which has a fuel tank (18), a fuel vapor storage device (25) for storing the escaping fuel vapors and a controllable valve (28) for adjusting the stream of fuel vapors fed to the intake tract (4) during a period of tank ventilation, the valve (28) is controlled in such a way according to the method that the stream of fuel vapors varies during the tank ventilation period. The regeneration of the fuel vapor storage device is intended to be improved thereby.

Abstract: A regulating method and a regulating device for actuating an actuator in an injection system for an internal combustion engine, may have the following steps: stipulation of a setpoint value for a controlled variable of the actuator; determination of an actual value of the controlled variable; determination of a setpoint/actual value deviation between the setpoint value and the actual value of the controlled variable; pilot control of a controlled variable in accordance with a predefined pilot control response as a function of the setpoint value; regulation of the controlled variable by a regulator output variable in accordance with a predefined regulating response as a function of the feedback setpoint/actual value deviation; actuation of the actuator with the pilot-controlled and regulated controlled variable; and determination of a characteristic variable of the injection system as a function of the regulator output variable.

Abstract: In a method for diagnosing an injection valve (5), in an overrun fuel cut-off phase the fuel supply to the fuel rail (4) is closed, and after the fuel supply has been closed off a first fuel pressure in the fuel rail (4) is measured, and after the first measurement of the fuel pressure an injection valve (5) is actuated for a test injection. After the test injection a second fuel pressure in the fuel rail (4) is measured, a differential pressure value (?P) is formed from the first and second measured fuel pressures and a difference of an operating parameter from a reference parameter is determined from the differential pressure value (?P), and when a previously defined maximum difference is exceeded the injection valve (5) is detected as being defective.

Abstract: A tank ventilating valve is disposed in a regeneration pipe which connects a storage container collecting fuel gas of a fuel tank to an intake pipe of the internal combustion engine. The tank ventilation system is air tightly sealed towards the atmosphere prevailing outside the motor vehicle while the tank ventilating valve is opened to create a negative pressure in the tank ventilation system. The method has the following steps: determining the fuel gas charge of the storage container; determining the volume flow rate through the tank ventilating valve; calculating an intermediate value from the product of the load and the volume flow rate; determining a tank pressure difference between the pressure prevailing in the fuel tank and the atmospheric pressure; and determining the additive corrective value by adjusting the intermediate value to the amount of the tank pressure difference.

Abstract: In a regulating method for controlling an electrical actuator, especially a valve for regulating a volume flow in an injection system for an internal combustion engine, a nominal value is set for an actuating variable of the actuator; the actuator is controlled by a pulse width-modulated electrical control signal with a pre-defined pulse duty factor and a pre-defined period for adjusting the desired nominal value of the actuating variable; a flow threshold value is determined according to the pre-defined nominal value for the actuating variable; the flow flowing through the actuator is continuously measured during the control by the control signal and before the end of the period; the measured flow is compared with the flow threshold value/and the flow flowing through the actuator is switched off before the end of the period of the control signal if the measured flow exceeds the current threshold value.

Abstract: In known methods for carrying out a high-pressure start of an internal combustion engine, inconvenient starting behaviour can sometimes occur. A method for carrying out a high-pressure start of an internal combustion engine (1) is provided, in which method a high-pressure pump (22) is used to feed fuel from a fuel tank (17) to a pressure accumulator (20) and a pressure adjusting means (23) is used to control the pressure in the pressure accumulator (20)), wherein the high-pressure pump (22) is operated before carrying out a fuel injection into a combustion chamber of the internal combustion engine (1), and the pressure adjusting means (23) is activated in such a way that, during the operation of the high-pressure pump (22), the pressure build-up in the pressure accumulator (20) above a pressure limit value pTHRES, upon the exceedance of which the fuel injection is enabled, is retarded.

Abstract: The invention relates to a method for functionally testing a filling level sensor which measures the filling level of a liquid in a tank, in which method a change in filling level that is measured by the filling level sensor is compared with a calculated change in filling level. According to the invention, the calculated change in filling level is determined from a measured change in temperature of the liquid.

Abstract: In a control method for an internal combustion engine (1) which has a fuel tank (18), a fuel vapor storage device (25) for storing the escaping fuel vapors and a controllable valve (28) for adjusting the stream of fuel vapors fed to the intake tract (4) during a period of tank ventilation, the valve (28) is controlled in such a way according to the method that the stream of fuel vapors varies during the tank ventilation period. The regeneration of the fuel vapor storage device is intended to be improved thereby.

Abstract: A tank ventilating valve is disposed in a regeneration pipe which connects a storage container collecting fuel gas of a fuel tank to an intake pipe of the internal combustion engine. The tank ventilation system is air tightly sealed towards the atmosphere prevailing outside the motor vehicle while the tank ventilating valve is opened to create a negative pressure in the tank ventilation system. The method has the following steps: determining the fuel gas charge of the storage container; determining the volume flow rate through the tank ventilating valve; calculating an intermediate value from the product of the load and the volume flow rate; determining a tank pressure difference between the pressure prevailing in the fuel tank and the atmospheric pressure; and determining the additive corrective value by adjusting the intermediate value to the amount of the tank pressure difference.

Abstract: An internal combustion engine has an intake duct, which opens into at least one inlet of at least one cylinder. It also has a tank purging valve, which is configured to control the initiation of a tank purging flow into the intake duct at an inlet point upstream of the respective inlet of the respective cylinder. A main path is configured in the intake duct and a recirculation path is configured there with a recirculation control element, a recirculation inlet from the main path into the recirculation path and a recirculation outlet from the recirculation path into the main path. The recirculation outlet is disposed in the main path upstream in relation to the recirculation inlet. A cylinder tank purging fuel mass is determined as a function of an opening angle of the tank purging valve and an opening angle of the recirculation control element.

Abstract: An internal combustion engine has an intake duct, which opens into at least one inlet of at least one cylinder. It also has a tank purging valve, which is configured to control the initiation of a tank purging flow into the intake duct at an inlet point upstream of the respective inlet of the respective cylinder. A main path is configured in the intake duct and a recirculation path is configured there with a recirculation control element, a recirculation inlet from the main path into the recirculation path and a recirculation outlet from the recirculation path into the main path. The recirculation outlet is disposed in the main path upstream in relation to the recirculation inlet. A cylinder tank purging fuel mass is determined as a function of an opening angle of the tank purging valve and an opening angle of the recirculation control element.

Abstract: The invention relates to a device for determining the quality of fuel for an internal combustion engine, comprising a pressure sensor (1) for determining the pressure (p) inside a fuel tank and/or comprising a temperature sensor (4) for determining the temperature (T) inside a fuel tank. According to the invention, an evaluation unit (5) is provided for determining a quality value (Q), which depicts die quality of the fuel, based on the temperature (T) and/or the pressure (p) inside the fuel tank. Said evaluation unit is connected on the input side to the pressure sensor (1) and/or to the temperature sensor (4).

Abstract: The invention relates to an operating method for a regeneration valve of a fuel vapor retention system, particularly of a tank vent valve for regenerating an activated carbon filter during which the regeneration valve is controlled by a control signal, whereby the control signal corresponds to a designated valve position of the regeneration valve. The invention provides that the correlation between the control signal and the resulting valve position of the regeneration valve is determined during a calibration process.

Abstract: The invention relates to a method for regulating a fuel tank venting valve of a motor vehicle during leak testing of a fuel tank venting system where the fuel tank venting valve is arranged in a recovery line that connects a retention vessel to catch fuel vapors from a fuel tank to an inlet manifold of an operating internal combustion engine, comprising sealing the tank venting system from the atmosphere outside the motor vehicle, opening the fuel tank venting valve to expose the fuel tank and the tank venting system to a relative negative pressure present in the inlet manifold of the operating internal combustion engine and regulating the degree of opening of the tank venting valve based upon the external pressure, pA.

Abstract: The invention relates to a method for functionally testing a filling level sensor which measures the filling level of a liquid in a tank, in which method a change in filling level that is measured by the filling level sensor is compared with a calculated change in filling level. According to the invention, the calculated change in filling level is determined from a measured change in temperature of the liquid.