The disclosure relates to a method and a device for checking the functionality of a crankcase ventilation system of an internal combustion engine. The crankcase ventilation system includes two crankcase ventilation lines arranged between a crankcase outlet of a crankcase and an associated introduction point into an air path of the internal combustion engine, via which crankcase ventilation lines gas can be introduced from the crankcase into the air path. The method includes measuring a pressure in the crankcase, supplying the measured pressure values to a control unit, and calculating the gradient of the measured pressure. The method also includes performing a gradient check, checking whether the gradient satisfies a specified criterion, and returning to the measurement of the pressure if the gradient satisfies the specified criterion. The method also includes recording an entry in a fault memory if the gradient does not satisfy the specified criterion.

A method and a device for checking the functionality of a crankcase ventilation system of an internal combustion engine is provided. The system has a low-load vent line and a high-load vent line between a crankcase outlet of a crankcase and a respectively associated introduction point into an air path of the internal combustion engine, in which method and device the pressure prevailing in the crankcase is measured by a crankcase pressure sensor and is compared with a crankcase pressure modeled on the assumption of a fault-free crankcase ventilation system, and in which method and device information items regarding the presence of a fault and of an associated fault location in the crankcase ventilation system are determined from the comparison result.

A vehicle controller is provided. A first passage of a supply passage of a blow-by gas processing device is connected to a portion of an intake passage located downstream of a compressor of a forced-induction device. The first passage includes a connection portion connected to the intake passage. A portion of the first passage between the connection portion and a PCV valve is a passage downstream portion. A supercooling determination process determines whether the supply passage is supercooled by relative wind of a vehicle based on a travel speed of the vehicle. An operating state changing process sets operation of the internal combustion engine to non-boosting operation when an ambient temperature of the vehicle is less than or equal to a determination temperature, the PCV valve is determined as being closed, and the supply passage is determined as being supercooled.

A vehicle controller is provided. A first passage of a supply passage of a blow-by gas processing device is connected to a portion of an intake passage located downstream of a compressor of a forced-induction device. The first passage includes a connection portion connected to the intake passage. A portion of the first passage between the connection portion and a PCV valve is a passage downstream portion. A supercooling determination process determines whether the supply passage is supercooled by relative wind of a vehicle based on a travel speed of the vehicle. An operating state changing process sets operation of the internal combustion engine to non-boosting operation when an ambient temperature of the vehicle is less than or equal to a determination temperature, the PCV valve is determined as being closed, and the supply passage is determined as being supercooled.

Provided is a diagnosis device for an internal combustion engine where the internal combustion engine includes a blow-by gas passage through which blow-by gas flows and the diagnosis device includes a temperature sensor which detects a temperature inside the blow-by gas passage and an abnormality detection unit which detects an abnormality in the internal combustion engine based on a detected value of the temperature sensor.

Systems, devices and methods for diagnosing malfunctioning in a crankcase ventilation (CCV) system are provided. A controller includes a processor and a memory storing instructions that cause the processor to: receive a plurality of pressure values including (i) a first pressure value indicative of a pressure of fluid flowing from a crankcase to a breather assembly of a system, (ii) a second pressure value indicative of a pressure of fluid flowing through a first tube coupled to the breather assembly, and (iii) a third pressure value indicative of a pressure of fluid flowing through a second tube coupled to the breather assembly; determine a pair of pressure differences based on the first pressure value, the second pressure value, and the third pressure value; and detect a malfunctioning in the CCV system based on the pair of pressure differences.

A blowby gas treatment device includes a pressure control valve, a fresh air induction pipe, a first blowby gas pipe, a second blowby gas pipe, a shutoff valve, a one-way valve, and a PCV valve. A leak diagnosis includes a first-stage diagnosis to determine whether or not falling of a pressure in a crank case after closing of the shutoff valve under a non-supercharging condition is normal. A second-stage diagnosis is implemented by moving the pressure control valve from a fully opened state into a fully closed state, and determining whether an intake air quantity in each state is equal to each other. When the intake air quantity in each state is equal to each other, presence of an in-system leak is determined. When a fully closed state intake air quantity is different from a fully opened state intake air quantity, presence of an out-of-system leak is determined.

Systems, devices and methods for diagnosing malfunctioning in a crankcase ventilation (CCV) system can include a controller receiving a plurality of pressure values. The plurality of pressure values include a first pressure value indicative of pressure of gases flowing between a crankcase and a breather assembly, a second pressure value indicative of pressure of gases flowing through a CCV tube from the breather assembly, and a third pressure value representing pressure of gases in a tube connected to the CCV tube. The controller can calculate a pair of pressure differences including a first pressure difference between the first pressure value and the second pressure value and a second pressure difference between the first pressure value and the third pressure value. The controller can detect a malfunctioning or defect in the CCV system based on the pair of pressure differences falling within a predefined clustering region.

An anomaly diagnostic device for an onboard internal combustion engine includes a parameter deriving unit and a leaking anomaly diagnostic unit. The parameter deriving unit is configured to derive a determination parameter such that, when a PCV pressure sensor value that indicates a pressure detected by a PCV pressure sensor is less than an atmospheric pressure, a value of the determination parameter increases as the difference between the PCV pressure sensor value and the atmospheric pressure increases. The leaking anomaly diagnostic unit is configured to perform a leaking anomaly diagnostic process that diagnoses that there is an anomaly at a portion of a blow-by gas passage that is closer to an intake passage than to a connection portion of the PCV pressure sensor when the determination parameter derived when an intake air amount changes is less than a threshold.

Systems, devices and methods for diagnosing malfunctioning in a crankcase ventilation (CCV) system can include a controller receiving a plurality of pressure values. The plurality of pressure values include a first pressure value indicative of pressure of gases flowing between a crankcase and a breather assembly, a second pressure value indicative of pressure of gases flowing through a CCV tube from the breather assembly, and a third pressure value representing pressure of gases in a tube connected to the CCV tube. The controller can calculate a pair of pressure differences including a first pressure difference between the first pressure value and the second pressure value and a second pressure difference between the first pressure value and the third pressure value. The controller can detect a malfunctioning or defect in the CCV system based on the pair of pressure differences falling within a predefined clustering region.