Patent ID: 11965444
Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F  Y | IPC F

Claim 0:
1. A controller for an internal combustion engine, wherein
an exhaust purification device is disposed in an exhaust passage of the internal combustion engine,
the internal combustion engine is configured to execute a fuel cutoff operation in which an engine output shaft is rotated with fuel supply stopped,
the controller comprises processing circuitry,
the processing circuitry is configured to execute a first change amount calculating process, a second change amount calculating process, a determination process, and an anomaly diagnosing process,
the first change amount calculating process is a process of calculating a first change amount that is a change amount per unit time of an upstream-side temperature, the upstream-side temperature being a temperature of exhaust gas on an upstream side of the exhaust purification device,
the second change amount calculating process is a process of calculating a second change amount that is a change amount per unit time of a downstream-side temperature, the downstream-side temperature being a temperature of exhaust gas on a downstream side of the exhaust purification device,
the determination process is a process of determining that a deviation between the first change amount during the fuel cutoff operation and the second change amount during the fuel cutoff operation is less than or equal to a threshold,
the anomaly diagnosing process is a process of determining that the exhaust purification device is in a detached state when it is determined in the determination process that the deviation is less than or equal to the threshold,
the processing circuitry is configured to interrupt the determination process when the upstream-side temperature increases within a determination period, and
the determination period is a period from when the determination process is started to when the upstream-side temperature decreases by a specified temperature from a value at the start of the determination process.