The invention relates to a method and a device, in particular a control and evaluation unit, for operating at least one exhaust gas sensor for monitoring the functionality of an emission control system in the exhaust tract of an internal combustion engine, wherein the exhaust gas sensor is operated at least intermittently at high temperatures and has a thermal shock sensitivity inherent to the design, and in which a heating phase can be implemented at least intermittently prior to a regeneration phase or prior to a measuring operation phase, wherein a clearly lower temperature is set in this heating phase in comparison to the regeneration temperature or the measuring operation temperature. According to the invention, the function for dew point recognition and re-release of a dew point end is adaptively implemented and influenced by at least one water detection criterion or at least one flood detection criterion. By this means, an improved dew point detection is achieved after driving through water, as a result of a significant reduction of tolerances and an earlier release of the dew point end for the exhaust gas sensor.

A method and an apparatus for heating a lambda detector of mild hybrid electric vehicle may include determining whether a measured value of the lambda detector is equal to or greater than a first reference value or is equal to or less than a second reference value when an overrun condition is satisfied; determining a first difference value between the measured value of the lambda detector and the first reference value and a second difference value between the measured value and the second reference value when the measured value of the lambda detector is equal to or greater than the first reference value or is equal to or less than the second reference value; determining a heating temperature and time according to the first difference value and the second difference value; and heating the lambda detector according to the determined heating temperature and time when a coasting condition is satisfied.

A method for diagnosing the function of an exhaust gas sensor in an exhaust gas. The function is evaluated here according to whether during a heating phase an operating temperature of the exhaust gas sensor has been reached for a predefined time period. It is taken into account here whether during the heating phase sufficient heating power has been available to carry out a successful heating phase.

A control device for an internal combustion engine comprises an air-fuel ratio control part configured to control the air-fuel ratio of the exhaust gas and a heating control part configured to control the heating of the air-fuel ratio sensors. The heating control part controls the sensor heaters so that the temperature of the upstream air-fuel ratio sensor becomes less than the activation temperature and so that the temperature of the downstream air-fuel ratio sensor becomes the activation temperature or more while the internal combustion engine is stopped by the automatic stop function. The air-fuel ratio control part controls the exhaust air-fuel ratio based on the outputs of the two air-fuel ratio sensors during engine operation and control the air-fuel ratio temporarily based on only the output of the downstream air-fuel ratio sensor after the internal combustion engine has been restarted after automatic stop.

An engine control device of a vehicle engine includes a processor that detects an operation state of the engine and controls an output of a heater which heats an intake air oxygen concentration sensor detecting oxygen concentration of intake air of the engine. The intake air includes a portion of exhaust gas recirculated to an intake passage of the engine as EGR gas. The processor controls the output of the heater, according to a detected operation state of the engine, so that the intake air oxygen concentration sensor enters one of (i) an active state where a temperature of the intake air oxygen concentration sensor becomes greater than or equal to an activation temperature, (ii) a semi-active state where the sensor temperature is lower than the activation temperature and higher than an inactivation temperature, and (iii) an inactive state where the sensor temperature is lower than the inactivation temperature.

Methods and systems are provided sensing particulate matter by a particulate matter (PM) sensor positioned downstream of a diesel particulate filter (DPF) in an exhaust system, where the PM sensor may include plurality of individual electrode pairs coupled to plurality of voltage sources and further to plurality of measurement devices. In one example, a method may include determining a total PM sensor current by summing current generated across the plurality of electrode pairs by determining the sum total of the current generated across the individual electrode pairs. In this way, the PM sensor may detect PMs in the exhaust more accurately, and not be affected by large particulates depositing on the electrodes.

A method for checking the function of a sensor for detecting soot is provided, the sensor including at least two measuring electrodes situated on a substrate made of an electrically insulating material, and a heating element, the method including: carrying out a first current-voltage measurement at a first temperature to ascertain a first measured variable, carrying out a second current-voltage measurement at a second temperature to ascertain a second measured variable, and forming a difference between the first measured variable and the second measured variable.

A sensor control device for connection to an oxygen sensor including a sensing element that measures oxygen concentration in an intake atmosphere of an internal combustion engine and a heater that heats the sensing element, including a detection unit that detects an output signal corresponding to the oxygen concentration output from the sensing element and a calculation unit that calculates a compensation coefficient of the output signal that is used when calculating the oxygen concentration. The calculation unit collects compensation information used in calculating the compensation coefficient when the internal combustion engine is in operation and in a specific operation state in which the oxygen concentration in the intake atmosphere is subject to estimation. Also disclosed is a sensor control system which includes an oxygen sensor and the sensor control device.

An apparatus for controlling an oxygen sensor may include an oxygen sensor configured to measure the exhaust gas which is generated by the combustion of the engine to generate an oxygen signal, and a controller configured to detect, through the oxygen sensor, a lag of the oxygen signal having responsiveness which is reduced depending on an oxygen amount of the exhaust gas, store information on occurrence factors which cause the lag of the oxygen signal, and increase a current heating quantity of a corresponding specific region about the occurrence factors to reconfirm whether the oxygen signal lags and determine the oxygen sensor as a failure or release a failure detection for the oxygen sensor.

A fuel gas composition sensing system may include a remotely controllable valve, with the valve including a gas inlet port, a gas outlet port, an internal chamber, and at least one actuating mechanism configured for successively opening the inlet port to allow gas to enter the internal chamber, closing the inlet port and the outlet port to retain the gas in the internal chamber for a period of time, and opening the outlet port to release the gas from the internal chamber. One or more micro-sensors may be mounted in the internal chamber of the valve, with each of the micro-sensors being configured to sense a characteristic of a gas introduced into the internal chamber of the valve. One or more heating elements may be mounted in the internal chamber, with each of the heating elements being associated with one of the one or more micro-sensors, and the one or more heating elements may be configured to implement a different temperature level at each of the micro-sensors in order to enable detection of a resulting change in the characteristic of the gas corresponding to a thermodynamic property of the gas that correlates to a composition of the gas.