A method for operating a nitrogen oxide sensor of a vehicle having a first nitrogen oxide sensor, a second nitrogen oxide sensor and a catalytic converter, one of the first and second nitrogen oxide sensors being arranged upstream of the catalytic converter with respect to the exhaust gas flow direction, and the other of the first and second nitrogen oxide sensors being arranged downstream of the catalytic converter, includes: determining a first characteristic value of the first nitrogen oxide sensor; determining a second characteristic value of the second nitrogen oxide sensor; determining a ratio of the first characteristic value to the second characteristic value; and adapting a sensor measured value of the second nitrogen oxide sensor in accordance with the ratio of the first characteristic value to the second characteristic value.

The present invention relates to a control device and to a control method for a vehicle drive mechanism including a moving body having a movability range regulated by two stoppers, and a sensor which senses a position of the moving body. The control device of the present invention learns an output of the sensor corresponding to a contact state of a high-rigidity stopper, and limits, to a lower level, an operation variable of the actuator for moving the moving body toward a low-rigidity stopper along with an increase in an amount of change in the output of the sensor from the contact state of the high-rigidity stopper. Then, the control device learns the output of the sensor corresponding to the contact state of the low-rigidity stopper, and controls the actuator based on the output of the sensor learned at both the stopper positions.

Various embodiments include a method for operating an internal combustion engine with a three-way catalytic converter with lambda control, comprising: monitoring a NO. sensor for a lambda value downstream of the converter; setting a threshold value determining a lambda setpoint value upstream of the converter using the difference between the setpoint value of the electrical signal and the measured electrical signal if the signal is below the threshold; if above the threshold value, determining the lambda setpoint value upstream of the converter using the difference between a NH.sub.3 setpoint value of the NO. sensor and the measured NH.sub.3 signal of the NO. sensor; and if the measured NH.sub.3 concentration is higher than the NH.sub.3 setpoint value, increasing the lambda setpoint value upstream of the converter and, if the measured NH.sub.3 concentration is lower than the NH.sub.3 setpoint value, reducing the lambda setpoint value upstream of the converter.

A control system of an internal combustion engine comprises an air-fuel ratio sensor 40, 41 detecting an air-fuel ratio of exhaust gas, a current detecting device 61 detecting an output current of the air-fuel ratio sensor, a voltage applying device 60 applying voltage to the air-fuel ratio sensor, and a voltage control part 81 configured to control voltage applied to the air-fuel ratio sensor through the voltage applying device. The voltage control part is configured to set the applied voltage to a reference voltage determined so that the output current becomes zero when an air-fuel ratio of inflowing exhaust gas flowing into the air-fuel ratio sensor is a stoichiometric air-fuel ratio, and correct the reference voltage so that the output current detected by the current detecting device becomes zero when it is judged that the air-fuel ratio of the inflowing exhaust gas is the stoichiometric air-fuel ratio.

Methods and systems are provided for a battery supplying power to an exhaust oxygen sensor heater. In one example, a method may include estimating a power delivered to the heater during heating of the sensor and in response to a power delivered from a battery being lower than a threshold, adjusting a battery charging strategy prior to an immediately subsequent engine start.

A method and system for estimating air mass per cylinder of an internal combustion engine is provided. An output signal from a MAF sensor is digitally processed to provide an estimate air mass per cylinder (APC). The system includes the MAF sensor; a data acquisition unit configured to receive an output signal from the MAF sensor and produce a sampled signal having a sampling rate greater than one sample per firing event; a multiple band pass (MBP) filter configured to remove signal components caused by airflow pulsations and oscillations through the MAF sensor; an envelope detector configured to detect the lower and upper envelopes of the MBP filtered signal; a MAF estimator configured to estimate a mass airflow based on the detected lower and upper envelopes; a signal decimator; a low pass filter; and a APC converter to converted the low pass filtered signal into an estimated APC.

A controller for an internal combustion engine includes processing circuitry. The processing circuitry is configured to execute an inflow process when an oxygen storage amount of the catalyst is greater than or equal to a predetermined amount. The inflow process includes operating the fuel injection valve to cause a fluid containing oxygen and unburned fuel to flow into the catalyst. An amount of the unburned fuel is greater than or equal to an ideal amount of unburned fuel that reacts with all of the oxygen. The processing circuitry is configured to execute, based on a detection value of the air-fuel ratio sensor obtained during an execution of the inflow process, a deviation amount calculation process that calculates a deviation amount indication value that indicates a deviation amount of a detection value of the air-fuel ratio sensor.

A control support device for supporting control of a vehicle using a learned model obtained by machine learning, includes: a data acquisition unit acquiring sensor information, which is related to a state of an inside or an outside of a supplying vehicle that supplies parameters to be used for the machine learning; a learning unit generating a learned model by performing the machine learning using an input/output data set, which is the sensor information acquired by the data acquisition unit and is data including input parameters and an output parameter of the learned model; and a transmission unit Transmitting at least one of the generated learned model and an output parameter calculated by inputting sensor information of the vehicle, control of which is supported, to the generated learned model as an input parameter.

Methods and systems are disclosed for operating an engine that includes a knock control system. The method and system may increase opportunities to learn one or more engine knock background noise levels via changing poppet valve timing and/or fuel injection timing. The method and system may also improve knock detection if knock sensor degradation is suspected.

Methods and systems are provided for diagnosing operation of a catalyst in the presence of oxygen sensor degradation over a vehicle life cycle. The methods and systems described herein filter the output of one oxygen sensor according to a time constant of a different oxygen sensor so that determination of a catalyst index ratio is compensated for oxygen sensor degradation.