Abstract: An exhaust gas sensor abnormality diagnostic device includes an exhaust gas sensor, and a judgment means that judges whether execution conditions are established for making an abnormality diagnosis of element breakage in the exhaust gas sensor. The device also includes an abnormality diagnosis means that makes the abnormality diagnosis in accordance with an output signal generated by the exhaust gas sensor. Further, when the integrated value of intake air amounts of an internal combustion engine is not smaller than a predetermined value, the judgment means judges that the execution conditions are established. The abnormality diagnosis means cancels the establishment of the execution conditions when an intake air amount of the internal combustion engine remains less than a predetermined value for a predetermined period of time.

Abstract: An exhaust gas sensor abnormality diagnostic device includes an exhaust gas sensor, and a judgment means that judges whether execution conditions are established for making an abnormality diagnosis of element breakage in the exhaust gas sensor. The device also includes an abnormality diagnosis means that makes the abnormality diagnosis in accordance with an output signal generated by the exhaust gas sensor. Further, when the integrated value of intake air amounts of an internal combustion engine is not smaller than a predetermined value, the judgment means judges that the execution conditions are established. The abnormality diagnosis means cancels the establishment of the execution conditions when an intake air amount of the internal combustion engine remains less than a predetermined value for a predetermined period of time.

Abstract: An exhaust gas sensor abnormality diagnostic device includes an exhaust gas sensor, and a judgment means that judges whether execution conditions are established for making an abnormality diagnosis of element breakage in the exhaust gas sensor. The device also includes an abnormality diagnosis means that makes the abnormality diagnosis in accordance with an output signal generated by the exhaust gas sensor. Further, when the integrated value of intake air amounts of an internal combustion engine is not smaller than a predetermined value, the judgment means judges that the execution conditions are established. The abnormality diagnosis means cancels the establishment of the execution conditions when an intake air amount of the internal combustion engine remains less than a predetermined value for a predetermined period of time.

Abstract: An exhaust gas sensor abnormality diagnostic device includes an exhaust gas sensor, and a judgment means that judges whether execution conditions are established for making an abnormality diagnosis of element breakage in the exhaust gas sensor. The device also includes an abnormality diagnosis means that makes the abnormality diagnosis in accordance with an output signal generated by the exhaust gas sensor. Further, when the integrated value of intake air amounts of an internal combustion engine is not smaller than a predetermined value, the judgment means judges that the execution conditions are established. The abnormality diagnosis means cancels the establishment of the execution conditions when an intake air amount of the internal combustion engine remains less than a predetermined value for a predetermined period of time.

Abstract: An air-fuel ratio sensor that outputs a sensor signal used for the feedback control of an air-fuel ratio is provided. It is determined whether an element crack is present by applying a reverse voltage to the air-fuel ratio sensor. The value of the sensor signal output from the air-fuel ratio sensor is corrected during a time period “A”. The time period “A” consists of a reverse-voltage application time period in which the reverse voltage is applied, and a return time period “T” after application of the reverse voltage ends. The return time period “T” is set based on sensor impedance correlated with the internal resistance of the air-fuel ratio sensor. The return time period “T” decreases as the sensor impedance decreases.

Abstract: An air-fuel ratio sensor that outputs a sensor signal used for the feedback control of an air-fuel ratio is provided. It is determined whether an element crack is present by applying a reverse voltage to the air-fuel ratio sensor. The value of the sensor signal output from the air-fuel ratio sensor is corrected during a time period “A”. The time period “A” consists of a reverse-voltage application time period in which the reverse voltage is applied, and a return time period “T” after application of the reverse voltage ends. The return time period “T” is set based on sensor impedance correlated with the internal resistance of the air-fuel ratio sensor. The return time period “T” decreases as the sensor impedance decreases.