Abstract: An abnormality diagnosis apparatus is an abnormality diagnosis apparatus for a pressure sensor provided in a purge passage that provides communication between an intake passage of an internal combustion engine and a canister, the pressure sensor being closer to the intake passage than a purge valve and a check valve are, the purge valve opening and closing the purge passage, the abnormality diagnosis apparatus for the pressure sensor including: a first determination unit that determines whether the purge valve is being kept in a closing state and a fuel cut in which fuel injection in the internal combustion engine is stopped is being executed; and a second determination unit that determines whether the pressure sensor is abnormal, based on a detection value of the pressure sensor, when the positive determination is made by the first determination unit.

Abstract: An anomaly diagnosing apparatus is adapted for a cooling device in an internal combustion engine. The apparatus is configured to execute an enlarging process, a rate calculating process, and an anomaly determining process. The enlarging process includes enlarging the cross-sectional area of the flow passage between an inner channel and an outer channel in the cooling device. The rate calculating process includes calculating a reference rate for a rate of rise of temperature of cooling water. The anomaly determining process includes determining that an anomaly is present in the check valve if a rate of rise of a detection value of cooling water temperature is smaller than the reference rate. The rate calculating process includes calculating the reference rate such that the reference rate has a smaller value in a case where the enlarging process is executed than in a case where the enlarging process is not executed.

Abstract: A control device for the internal combustion engine includes a pulsation detector, a path length calculator, and an anomaly detector. The pulsation detector detects the pulsation of the intake air flowing through the intake passage based on output signals from the air flowmeter. The path length calculator calculates the path length, which is a parameter that is correlated with the degree of the pulsation, based on the pulsation of the intake air detected by the pulsation detector. The anomaly detector determines that the fresh air passage is detached if the path length calculated by the path length calculator is less than or equal to a determination value and detects an anomaly in the fresh air passage.

Abstract: An evaporated fuel treating device includes a canister, a first purge passage connected to the canister, a second purge passage connected to a second end of the first purge passage and an intake passage, a purge control valve disposed in the first purge passage, a pulsation detection sensor disposed in the second purge passage, and an electronic control unit configured to execute abnormality detection control that detects abnormality of the second purge passage. The electronic control unit is configured to detect pulsation of a purge gas flowing through the second purge passage, based on an output signal from the pulsation detection sensor when the electronic control unit execute a control that opens and closes the purge control valve, and determine abnormality of the second purge passage, based on the detected pulsation.

Abstract: An anomaly diagnosing apparatus is adapted for a cooling device in an internal combustion engine. The apparatus is configured to execute an enlarging process, a rate calculating process, and an anomaly determining process. The enlarging process includes enlarging the cross-sectional area of the flow passage between an inner channel and an outer channel in the cooling device. The rate calculating process includes calculating a reference rate for a rate of rise of temperature of cooling water. The anomaly determining process includes determining that an anomaly is present in the check valve if a rate of rise of a detection value of cooling water temperature is smaller than the reference rate. The rate calculating process includes calculating the reference rate such that the reference rate has a smaller value in a case where the enlarging process is executed than in a case where the enlarging process is not executed.

Abstract: A control device for the internal combustion engine includes a pulsation detector, a path length calculator, and an anomaly detector. The pulsation detector detects the pulsation of the intake air flowing through the intake passage based on output signals from the air flowmeter. The path length calculator calculates the path length, which is a parameter that is correlated with the degree of the pulsation, based on the pulsation of the intake air detected by the pulsation detector. The anomaly detector determines that the fresh air passage is detached if the path length calculated by the path length calculator is less than or equal to a determination value and detects an anomaly in the fresh air passage.

Abstract: An evaporated fuel treating device includes a canister, a first purge passage connected to the canister, a second purge passage connected to a second end of the first purge passage and an intake passage, a purge control valve disposed in the first purge passage, a pulsation detection sensor disposed in the second purge passage, and an electronic control unit configured to execute abnormality detection control that detects abnormality of the second purge passage. The electronic control unit is configured to detect pulsation of a purge gas flowing through the second purge passage, based on an output signal from the pulsation detection sensor when the electronic control unit execute a control that opens and closes the purge control valve, and determine abnormality of the second purge passage, based on the detected pulsation.

Abstract: An abnormality diagnosis apparatus is an abnormality diagnosis apparatus for a pressure sensor provided in a purge passage that provides communication between an intake passage of an internal combustion engine and a canister, the pressure sensor being closer to the intake passage than a purge valve and a check valve are, the purge valve opening and closing the purge passage, the abnormality diagnosis apparatus for the pressure sensor including: a first determination unit that determines whether the purge valve is being kept in a closing state and a fuel cut in which fuel injection in the internal combustion engine is stopped is being executed; and a second determination unit that determines whether the pressure sensor is abnormal, based on a detection value of the pressure sensor, when the positive determination is made by the first determination unit.

Abstract: An apparatus for detecting imbalance abnormality in an air-fuel ratio between cylinders in a multi-cylinder internal combustion engine is disclosed. The apparatus includes an imbalance determining unit programmed to determine imbalance in an air-fuel ratio of a first cylinder belonging to a cylinder group based upon a difference value between an index value correlative with a crank angular speed detected in the first cylinder and an index value correlative with a crank angular speed detected in a second cylinder belonging to another cylinder group, and further a correction unit programmed to correct the difference value for the first cylinder based upon the index value detected in at least one of other cylinders belonging to the same cylinder group as that of the first cylinder.

Abstract: An inter-cylinder air-fuel ratio variation abnormality detection apparatus is disclosed. The apparatus determines imbalance of an air-fuel ratio among the cylinders based on a difference between index values correlated with crank angular velocities detected in a set of opposite cylinders belonging to different banks and having crank angles different from one another by 360°; and carries out an air-fuel ratio feedback process for controlling an amount of injected fuel for each of the banks, wherein the apparatus comprises a correction unit correcting, before determining the air-fuel ratio imbalance, the difference between the index values in a direction of combustion improvement for opposite cylinders that are opposite to cylinders belonging to a bank identical to a bank of a cylinder with the most deviating index value from a standard value among all the cylinders and being other than the cylinder with the most deviating index value.

Abstract: An apparatus for detecting imbalance abnormality in an air-fuel ratio between cylinders in a multi-cylinder internal combustion engine is disclosed. The apparatus includes an imbalance determining unit programmed to determine imbalance in an air-fuel ratio of a first cylinder belonging to a cylinder group based upon a difference value between an index value correlative with a crank angular speed detected in the first cylinder and an index value correlative with a crank angular speed detected in a second cylinder belonging to another cylinder group, and further a correction unit programmed to correct the difference value for the first cylinder based upon the index value detected in at least one of other cylinders belonging to the same cylinder group as that of the first cylinder.

Abstract: Provided is an apparatus for detecting cylinder air-fuel ratio imbalance abnormality. The apparatus is provided with an abnormality detecting unit that detects a cylinder air-fuel ratio imbalance abnormality by comparing a value of a parameter correlated with a degree of fluctuation in the air-fuel ratio sensor output to an abnormality threshold value, and a correcting unit that corrects at least one of the value of the parameter or the abnormality threshold value on the basis of atmospheric pressure. An amount of correction performed by the correcting unit is modified according to engine load.

Abstract: An inter-cylinder air-fuel ratio variation abnormality detection apparatus is disclosed. The apparatus determines imbalance of an air-fuel ratio among the cylinders based on a difference between index values correlated with crank angular velocities detected in a set of opposite cylinders belonging to different banks and having crank angles different from one another by 360°; and carries out an air-fuel ratio feedback process for controlling an amount of injected fuel for each of the banks, wherein the apparatus comprises a correction unit correcting, before determining the air-fuel ratio imbalance, the difference between the index values in a direction of combustion improvement for opposite cylinders that are opposite to cylinders belonging to a bank identical to a bank of a cylinder with the most deviating index value from a standard value among all the cylinders and being other than the cylinder with the most deviating index value.