A learned neural network learned in weights using an engine load, an engine speed, and an intake pressure inside the engine intake passage downstream of the throttle valve (19) as input parameters of the neural network and using leakage of blow-by gas from a blow-by gas feed path (20) as a truth label is stored. At the time of operation of the vehicle, the learned neural network is used to detect the abnormality of leakage of blow-by gas from the blow-by gas feed path (20) from the above input parameters.

In a recirculation valve, a first support target portion receives a biasing force of a biasing member on a first stepped surface and moves to one side in an axial direction, such that a first opening is blocked. The first support target portion moves to the other side in the axial direction against a biasing force of the biasing member due to a negative pressure on a downstream side with respect to an upstream side, such that the first opening opens.

A unit (10) for the regulation or control of a fluid pressure, having at least one housing section (13, 14) and a switching film (22) connected to the at least one housing section (13, 14) for switching at pressure differentials relative to an ambient pressure acting on the switching film (22), and for the regulation, release or blocking of a flow of the fluid between an inlet (28) and a discharge (30) for the fluid. The switching film (22) is made out of a polymer material having fluorine and carbon, in particular a thermoplastic having fluorine and carbon. In this arrangement, a hole cross-section (40) of the at least one housing section (13, 14) is closed off by the switching film (22).

A leakage detection device detects leakage in a PCV passage that at least includes a scavenging line that communicates between a crank chamber of an engine and a portion of an intake passage of the engine that is on a downstream side of a throttle valve and a fresh air line that communicates between the crank chamber and a portion of the intake passage that is on an upstream side of the throttle valve. The leakage detection device includes a pressure measurement, a first valve and a leakage determination unit. The pressure measurement unit measures pressure in the PCV passage. The first valve opens/closes the fresh air line. The leakage determination unit determines presence or absence of leakage in the PCV passage on a basis of the pressure in the PCV passage at a time when the first valve is closed.

A blow-by gas treating device discharges blow-by gas into intake air. A controller selects and executes one of a fuel cutoff process and a fuel introduction process when stopping combustion in a cylinder under a situation in which a crankshaft of the internal combustion engine is rotating. An injection valve controlling section controls a fuel injection valve to regulate a fuel injection amount in a period in which the combustion in the cylinder is stopped under the situation in which the crankshaft is rotating. The injection valve controlling section decreases the fuel injection amount from the fuel injection valve as an oil temperature that is the temperature of engine oil increases.

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.

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.

A convergent nozzle is in a mixer housing and in a flow path from an air inlet of the mixer to an outlet of the mixer. A convergent-divergent nozzle is in the mixer housing and includes an air-exhaust gas inlet in fluid communication to receive fluid flow from the convergent nozzle and from the interior of the exhaust gas housing. A first nozzle module is configured to be received in the mixer housing and, when received in the mixer housing, define at least a portion of the convergent nozzle or the convergent-divergent nozzle. A second nozzle module is configured to be received in the mixer housing separate from the first nozzle module. The second nozzle module, when received in the mixer housing, is configured to define at least a portion of the convergent or the convergent-divergent nozzle. The second nozzle module has a different flow characteristic than the first nozzle module.

An abnormality determination apparatus for an internal combustion engine in which an intake passage upstream of a supercharger and a crankcase are connected by a breather line includes: an intake flow rate detection unit that detects an intake flow rate in the intake passage; and an abnormality determination unit that determines abnormality of the breather line. The abnormality determination unit accumulates a time for which a rotation second-order component of a fluctuation waveform of the intake flow rate is equal to or more than a threshold over a predetermined period of time and determines the abnormality of the breather line when the accumulated value is less than a predetermined accumulation threshold.

An abnormality determination apparatus for an internal combustion engine in which an intake passage upstream of a supercharger and a crankcase are connected by a breather line includes: an intake flow rate detection unit that detects an intake flow rate in the intake passage; and an abnormality determination unit that determines abnormality of the breather line. The abnormality determination unit accumulates a value calculated from a rotation second-order component of a fluctuation waveform of the intake flow rate over a predetermined period of time and determines the abnormality of the breather line when the accumulated value is less than a predetermined threshold.