A turbocharger is provided and includes a compressor housing and a recirculation slit and a recirculation passage provided at an inlet of the compressor housing to enable air flowing into the compressor to be recirculated. A gas supply part supplies blow-by gas towards the inlet of the compressor housing to allow blow-by gas to be joined with air recirculated through the recirculation slit and the recirculation passage and to guide recirculating air towards a compressor wheel.

A blow-by gas leak diagnostic device includes a first PCV flow path, a second PCV flow path, a fresh air inlet, a pressure measurement unit, a first valve that opens and closes the first PCV flow path, a second valve that opens and closes the second PCV flow path, a third valve that opens and closes the fresh air inlet, a valve control unit, and a leak diagnosis unit. The valve control unit controls an opening degree of the third valve when a downstream side of an intake manifold with respect to a throttle valve has a negative pressure, and the second valve is in a closed state. The leak diagnosis unit diagnoses presence or absence of a leak in the first PCV flow path on the basis of an inner pressure of the first PCV flow path measured by the pressure measurement unit.

The disclosure relates to a method for leakage diagnosis. The method includes influencing the introduction of gas along a crankcase aeration line into a crankcase of an internal combustion engine and acquiring a measurement signal profile by an exhaust-gas sensor arranged in an exhaust-gas tract of an internal combustion engine. The measurement signal profile is characteristic of at least one exhaust-gas property of the exhaust gas. The method includes providing an expected measurement signal profile which is characteristic of the exhaust-gas property of the exhaust gas in the exhaust-gas tract based on the influence on the introduction of gas into the crankcase. Additionally, the method includes comparing the acquired measurement signal profile with the expected measurement signal profile and identifying that the crankcase ventilation line has a leak if, during the comparison, the acquired measurement signal profile deviates from the expected measurement signal profile by a predetermined threshold value.

An abnormality determination device of an internal combustion engine in which a breather line connects an intake-air path positioned upstream from a forced-induction system and a crankcase includes an intake-air flow rate sensor that detects an intake air flow rate in the intake-air path, a pressure sensor that detects a pressure of the breather line, and an abnormality determination unit that determines abnormality of the breather line. The abnormality determination unit estimates an intake air resistance of the intake-air path from the pressure when the engine is under low load conditions under which the intake air flow rate is less than a predetermined value and the pressure when the engine is under high load conditions under which the intake air flow rate is the predetermined value or greater and determines abnormality of the breather line when the intake air resistance is less than a threshold.

An evaporated fuel treatment apparatus includes an abnormality determination unit that determines an abnormality of a purge passage. The abnormality determination unit changes an operating cycle of a purge control valve to a cycle longer than an initial set value while maintaining a duty ratio of the purge control valve set according to an operating state of an internal combustion engine, and determines an abnormality of the purge passage based on a first variation range and a second variation range calculated from a detection value detected by an airflow meter before and after the change of the operating cycle.

An engine includes: an exhaust manifold 7 close to one of left and right side surfaces of an engine; a turbocharger 60 having an exhaust-side inlet connected to the exhaust manifold 7; and a rocker-arm-chamber-integrated intake manifold 8 being disposed on an upper surface of a cylinder head 5 and integrally including a rocker arm chamber 90 and an intake manifold 6. The intake manifold 8 has a wall 101 dividing the rocker arm chamber 90 close to the one of the left and right side surfaces of the engine 1 and the intake manifold 6 close to the other of the left and right side surfaces to isolate the rocker arm chamber 90 and the intake manifold 6 from each other. The rocker arm chamber 90 has, in its upper portion, a positive crankcase ventilation device 69 protruding therefrom and being configured to return blowby gas to an intake system. The positive crankcase ventilation device 69 has, in its side surface, a blowby-gas discharge port 67 connected with a gas conduit 68 through which blowby gas is delivered to an intake-side inlet of the turbocharger 60.

The invention relates to an oil decantation system (1) comprising: (i) a separator device (6) designed to trap the oil droplets (107) that are present in a flow of a blow-by gas (110); and (ii) a jet pump (5) positioned upstream of the separator device (6) and designed to accelerate and draw the flow of the blow-by gas (110) before it enters said separator device (6).

A ventilation apparatus of an internal combustion engine of the invention ventilates a chain chamber by recirculating blow-by gas to an intake passage through a blow-by gas recirculation pipe and introducing air into the chain chamber through an air introduction pipe. The air introduction pipe is secured to a head cover wall portion which corresponds to a portion of a head cover wall which defines the chain chamber.

An internal combustion engine may be used to compress natural gas for vehicle fuel. The engine may contain a plurality of gas compression cylinders, at least one standard combustion cylinder to drive the compression cylinders, and a common crankshaft in a crankcase coupling the compression cylinders and the at least one standard combustion cylinder. Some combustible gas being compressed may leak past the piston rings of the compression cylinders into the engine crankcase posing a safety concern. This invention eliminates this concern by actively flushing the crankcase at a higher rate than normal.

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.