Abstract: A method for diagnosing a malfunction of a sensor system in an air system of an internal combustion engine, said sensor system comprising a first air state sensor, a second air state sensor and a third air state sensor, wherein a first value and a second value of a first comparison variable are ascertained in two different ways in an overall calculation step such that the result of a comparison between the first value and the second value is a function of each of the output variables of the first, second and third air state sensors and wherein in a fault detection step, said method recognizes as a function of the comparison between said first value and said second value of the comparison variable that a fault exists in the sensor system.

Abstract: A method for processing sensor signals in a control unit of a motor vehicle and a control unit for carrying out the method. The control unit is provided for the open-loop and/or closed-loop control of a system and acquires signals from this system. The system is modeled with the aid of a model, at least one value being ascertained for a slow signal based on the model.

Abstract: In a method for determining a low pressure exhaust gas recirculation mass flow {dot over (m)}Opt in the air system of an internal combustion engine (10) with low pressure exhaust gas recirculation, the determination of the low pressure exhaust gas recirculation mass flow {dot over (m)}Opt involves a preliminary low pressure exhaust gas recirculation mass flow {dot over (m)}EGRLPDs which is determined from a function involving, in particular, the pressure p42 upstream and the pressure p12 downstream of a low pressure side exhaust gas recirculation valve EGRVIvLP (29), the temperature TEGRVIvPUs downstream of the low pressure side exhaust gas recirculation valve (29), and the geometry arEGRVIvLP of the low pressure side exhaust gas recirculation valve (29). According to the invention, at least one mass balance based variable is also considered in the determination of the low pressure exhaust gas recirculation mass flow {dot over (m)}Opt.

Abstract: A drive system for a motor vehicle, having an internal combustion engine, an air and exhaust gas system, which includes at least one throttle, an exhaust gas recirculation system, which is in fluidic connection with the air and exhaust gas system at two connecting points, and a measuring device, which is designed to detect an atmospheric pressure, to detect a gas pressure at a measuring point within the air and exhaust gas system, and to ascertain a differential pressure as a function of the gas pressure and the atmospheric pressure, the measuring point being fluidically situated between the throttle and the internal combustion engine and in a region of one of the connecting points.

Abstract: A method and device for monitoring errors in an exhaust gas recirculation line, including supplying an engine with fresh air via a supply duct using a compressor, discharging exhaust gas via an exhaust duct using a gas turbine, a subflow of the gas being supplied from a low-pressure area of the exhaust duct downstream from the turbine, via the recirculation line, to an intake air low-pressure area of the supply duct upstream from the compressor, an exhaust gas mass flow of the subflow in the recirculation line is set via a valve, a fresh air mass flow being set by a fresh air throttle, or via an exhaust flap in the exhaust duct. Where the fresh air throttle or the exhaust flap is opened when the recirculation line is free of errors, an error in the recirculation line is deduced if the throttle or flap is at least partially closed.

Abstract: In a method for determining a low pressure exhaust gas recirculation mass flow in the air system of an internal combustion engine (10) with low pressure exhaust gas recirculation, the determination of the low pressure exhaust gas recirculation mass flow involves a preliminary low pressure exhaust gas recirculation mass flow which is determined from a function involving, in particular, the pressure p42 upstream and the pressure p12 downstream of a low pressure side exhaust gas recirculation valve EGRVIvLP (29), the temperature TEGRVIvPUs downstream of the low pressure side exhaust gas recirculation valve (29), and the geometry arEGRVIvLP of the low pressure side exhaust gas recirculation valve (29). According to the invention, at least one mass balance based variable is also considered in the determination of the low pressure exhaust gas recirculation mass flow .

Abstract: A method for monitoring a control loop or a regulating loop in a system, in particular in an engine system in a motor vehicle, is described. A characteristic value is ascertained from a preset value and a system variable of the regulating loop or the control loop during one or more state changes, and an error is detected as a function of the ascertained characteristic value.

Abstract: A method for diagnosing a malfunction of a sensor system in an air system of an internal combustion engine, said sensor system comprising a first air state sensor, a second air state sensor and a third air state sensor, wherein a first value and a second value of a first comparison variable are ascertained in two different ways in an overall calculation step such that the result of a comparison between the first value and the second value is a function of each of the output variables of the first, second and third air state sensors and wherein in a fault detection step, said method recognizes as a function of the comparison between said first value and said second value of the comparison variable that a fault exists in the sensor system.

Abstract: A method for providing a specification about an efficiency of a cooler for recirculated exhaust gas in an internal combustion engine includes: measuring a temperature of the recirculated exhaust gas cooled by the cooler; and ascertaining the specification about the efficiency of the cooler as a function of the measured temperature of the cooled recirculated exhaust gas. With the aid of the specification about the efficiency of the cooler it is possible to determine a failure of the cooler or to calculate a temperature of the recirculated exhaust gas in order implement an engine control system of the internal combustion engine on the basis of a reliable temperature specification that is not influenced by lag effects.

Abstract: A method and a device for operating an internal combustion engine having at least one mass flow line and a cooling device for cooling the mass flow in the mass flow line, as well as a bypass, having a bypass valve, that bypasses the cooling device. When the bypass valve is opened, the mass flow is conducted at least partly through the bypass. When the bypass valve is closed, the mass flow is conducted through the cooling device. Downstream from the cooling device and from the bypass in the mass flow line, a temperature of the mass flow in the mass flow line is determined. In at least one operating state of the internal combustion engine, a first temporal temperature gradient is determined with closed bypass valve. In the at least one operating state of the internal combustion engine, a second temporal temperature gradient is determined with closed position of the bypass valve.

Abstract: A method for the diagnosis of an exhaust gas recirculation system in an internal combustion engine, including providing a pressure difference reading, which gives a pressure difference in an air supply section of the internal combustion engine or a pressure difference over the exhaust gas recirculation system; determining a pressure difference reference value as a function of one or more operating variables of the internal combustion engine; and detecting a fault in the exhaust gas recirculation system as a function of the pressure difference reading and of the pressure difference reference value.

Abstract: A method for the diagnosis of an exhaust gas recirculation system in an internal combustion engine, including providing a pressure difference reading, which gives a pressure difference in an air supply section of the internal combustion engine or a pressure difference over the exhaust gas recirculation system; determining a pressure difference reference value as a function of one or more operating variables of the internal combustion engine; and detecting a fault in the exhaust gas recirculation system as a function of the pressure difference reading and of the pressure difference reference value.

Abstract: A method for providing a specification about an efficiency of a cooler for recirculated exhaust gas in an internal combustion engine includes: measuring a temperature of the recirculated exhaust gas cooled by the cooler; and ascertaining the specification about the efficiency of the cooler as a function of the measured temperature of the cooled recirculated exhaust gas. With the aid of the specification about the efficiency of the cooler it is possible to determine a failure of the cooler or to calculate a temperature of the recirculated exhaust gas in order implement an engine control system of the internal combustion engine on the basis of a reliable temperature specification that is not influenced by lag effects.

Abstract: A method for monitoring a control loop or a regulating loop in a system, in particular in an engine system in a motor vehicle, is described. A characteristic value is ascertained from a preset value and a system variable of the regulating loop or the control loop during one or more state changes, and an error is detected as a function of the ascertained characteristic value.

Abstract: A method and a device for operating an internal combustion engine having at least one mass flow line and a cooling device for cooling the mass flow in the mass flow line, as well as a bypass, having a bypass valve, that bypasses the cooling device. When the bypass valve is opened, the mass flow is conducted at least partly through the bypass. When the bypass valve is closed, the mass flow is conducted through the cooling device. Downstream from the cooling device and from the bypass in the mass flow line, a temperature of the mass flow in the mass flow line is determined. In at least one operating state of the internal combustion engine, a first temporal temperature gradient is determined with closed bypass valve. In the at least one operating state of the internal combustion engine, a second temporal temperature gradient is determined with closed position of the bypass valve.

Abstract: Provided are a method and device for operating an internal combustion engine having exhaust-gas recirculation, the method and device allowing a diagnosis of an exhaust-gas recirculation cooler during normal operation of the internal combustion engine. In this context, a variable characteristic of the functioning of the exhaust-gas recirculation cooler is monitored. The variable characteristic of the functioning of the cooling device is ascertained as a function of a measured value. The variable characteristic of the functioning of the exhaust-gas recirculation cooler is specified on the basis of an intact exhaust-gas recirculation cooler. The ascertained value of the variable characteristic of the functioning of the exhaust-gas recirculation cooler is compared to the predefined value. An error is detected when the ascertained value of the variable characteristic of the function of cooling device deviates from the specified value.

Abstract: Provided are a method and device for operating an internal combustion engine having exhaust-gas recirculation, the method and device allowing a diagnosis of an exhaust-gas recirculation cooler during normal operation of the internal combustion engine. In this context, a variable characteristic of the functioning of the exhaust-gas recirculation cooler is monitored. The variable characteristic of the functioning of the cooling device is ascertained as a function of a measured value. The variable characteristic of the functioning of the exhaust-gas recirculation cooler is specified on the basis of an intact exhaust-gas recirculation cooler. The ascertained value of the variable characteristic of the functioning of the exhaust-gas recirculation cooler is compared to the predefined value. An error is detected when the ascertained value of the variable characteristic of the function of cooling device deviates from the specified value.