Abstract: In a failure determination device for an internal combustion engine equipped with a supercharger, the failure determination device determining a failure of a breather pipe that is connected between a crankcase and an intake passage at a position on an upstream side of the supercharger, the breather pipe is constituted by a double pipe including an inner pipe and an outer pipe, a communication passage communicates an enclosed space between the inner pipe and the outer pipe of the breather pipe with a portion of the intake passage on a downstream side of the supercharger. When the detected breather outer-pipe gauge pressure is higher than or equal to a determination threshold that is set in accordance with detected intake gauge pressure, the failure determination device determines that the breather pipe is failed.

Abstract: An abnormality assessment device includes an on-off valve that shuts an intake path on an upstream side of a connection portion of a breather line with respect to the intake path and an abnormality assessment element that assesses abnormality of the breather line. The abnormality assessment element assesses abnormality of the breather line based on a difference between an intake flow rate that is detected by an intake flow rate sensor and a target intake flow rate in a case where the on-off valve is closed.

Abstract: In a failure determination device for an internal combustion engine equipped with a supercharger, the failure determination device determining a failure of a breather pipe that is connected between a crankcase and an intake passage at a position on an upstream side of the supercharger, the breather pipe is constituted by a double pipe including an inner pipe and an outer pipe, a communication passage communicates an enclosed space between the inner pipe and the outer pipe of the breather pipe with a portion of the intake passage on a downstream side of the supercharger. When the detected breather outer-pipe gauge pressure is higher than or equal to a determination threshold that is set in accordance with detected intake gauge pressure, the failure determination device determines that the breather pipe is failed.

Abstract: An internal combustion engine includes on-off valves that configure a closed space by closing an internal space of a breather line, a pump that depressurizes or pressurizes the closed space, a pressure sensor that detects a pressure of the closed space, and an abnormality assessment element that assesses abnormality of the breather line. The abnormality assessment element assesses abnormality of the breather line based on a pressure change of the closed space in a case where the closed space is depressurized or pressurized by the pump.

Abstract: An abnormality assessment device includes an on-off valve that shuts an intake path on an upstream side of a connection portion of a breather line with respect to the intake path and an abnormality assessment element that assesses abnormality of the breather line. The abnormality assessment element assesses abnormality of the breather line based on a difference between an intake flow rate that is detected by an intake flow rate sensor and a target intake flow rate in a case where the on-off valve is closed.

Abstract: An internal combustion engine includes on-off valves that configure a closed space by closing an internal space of a breather line, a pump that depressurizes or pressurizes the closed space, a pressure sensor that detects a pressure of the closed space, and an abnormality assessment element that assesses abnormality of the breather line. The abnormality assessment element assesses abnormality of the breather line based on a pressure change of the closed space in a case where the closed space is depressurized or pressurized by the pump.