This blow-by gas discharge device is provided with: blow-by gas piping 23 which is extended from the height position of the upper end of an internal combustion engine 1 to the height position of the lower end, is exposed to the outside air, and has an outlet 33 open to the atmosphere; and a heating chamber 24 which is provided between the ends of the blow-by gas piping, is formed in the flywheel housing 10 of the internal combustion engine, and heats blow-by gas.

An engine control device is provided, which includes a blowby gas passage connecting an engine body to an intake passage so that blowby gas leaked from a combustion chamber is recirculated to the intake passage, a boost pressure changer configured to change a boost pressure of a turbocharger, and a controller configured to set a target boost pressure and control the boost pressure changer. The turbocharger includes a turbine which is provided to an exhaust passage and driven by exhaust gas, and a compressor which is provided to the intake passage and rotary driven by the turbine to boost intake air. The blowby gas passage is connected to the intake passage near the compressor. The controller corrects the target boost pressure when an ambient temperature is below a given determination temperature, to be higher than the target boost pressure when the ambient temperature is at or above the determination temperature.

A heating device for an exhaust system of an internal combustion engine; the heating device has: a first tubular body wherein a combustion chamber is obtained; a fuel injector to inject fuel into the combustion chamber; an inlet opening, which is obtained through the first tubular body and can be connected to a fan to receive an air flow, which is directed into the combustion chamber; a hot air outlet opening to let hot air out of the combustion chamber; an outlet duct, which originates from the outlet opening; a spark plug which is mounted through a side wall of the first tubular body to trigger the combustion of a mixture of air and fuel; and a labyrinth, which surrounds a side wall of the tubular body, starts from the inlet opening, ends in the combustion chamber, and the air must necessarily flow out of the inlet opening until reaching the combustion chamber.

There is provided a blowby gas atmosphere releasing device 20 for an engine 1 in which an intake flow path 3 is disposed at one side of an engine body 2 and an exhaust flow path 4 is disposed at the other side. The blowby gas atmosphere releasing device 20 includes an oil separator 22 that is connected to the engine body 2 and separates oil contained in blowby gas, and an atmosphere releasing pipe 23 that is connected to the oil separator 22 and is used to release the blowby gas to the atmosphere. The atmosphere releasing pipe 23 is disposed along the other side of the engine body 2.

A positive crankcase ventilation (PCV) outlet anti-freezing device of an intake manifold of a vehicle engine includes a first guide and a second guide formed adjacent to a PCV outlet within an inlet tube of the intake manifold to block direct contact between fresh air and a PCV gas, thereby preventing condensation and freezing of the PCV gas. The first guide and the second guide also can improve flow distribution of the intake manifold by improving fluidity of the fresh air.

A blow-by gas return device includes: a gas path which is configured to introduce a blow-by gas generated in a crankcase into an intake system through an inside of a head cover, a pressure control valve and a blow-by pipe; and an orifice provided to the gas path, the orifice mounted on a wall portion of an intake manifold on a cylinder head side. A passage for a blow-by gas is formed in the wall portion on the cylinder head side, and the orifice is formed on a joint pipe mounted on the passage for the blow-by gas for communicably connecting the blow-by pipe with the passage for the blow-by gas.

An engine fluid heating apparatus, preventing failure in heating fluid, is provided. A control device opens a sub switch during an initial opening period (“IOP”) after closing a main switch, and the control device closes the sub switch during an initial closing period (“ICP”) after the IOP. Circuit normality is displayed by turning on an indicator lamp when a heater feeding circuit is electrically conducted via a bypass electric circuit during the IOP. Heater feeding is displayed by turning off the indicator lamp when power is supplied to the electric heater via a trunk electric circuit during the ICP. Circuit abnormality is displayed by turning off the indicator lamp when the heater feeding circuit is not electrically conducted via the bypass electric circuit during the IOP, and the circuit abnormality display is held by keeping the indicator lamp off during the ICP immediately after the IOP.

An engine unit including a heater provided in a blow-by gas returning path for returning a blow-by gas that leaks out from a combustion chamber of an engine to an intake path. The heater is electrically connected to a controller of the engine through wiring harnesses. The controller is configured to, while controlling energization of the heater, perform an abnormality detection on the wiring harness based on a magnitude of current flowing to the wiring harness during energization of the heater, and perform an abnormality detection on the heater and the wiring harnesses based on a magnitude of voltage applied to the wiring harness located downstream from the heater during non-energization of the heater.

A cylinder head cover that prevents the gas outlet for the blow-by gas from being cooled by structural improvements so that the gas outlet does not freeze or become clogged in a cold condition. A cylinder head cover includes: a gas passage through which blow-by gas from a crankcase passes; and a gas outlet portion protruding upward from a head cover upper wall. The gas outlet portion includes a protruding case portion bulging upward from the head cover upper wall so as to form an outlet passage through which blow-by gas passes, and an air layer is formed outside the outlet passage in the protruding case portion.

An intake manifold 10 includes: a surge tank 11 that is connected on an upstream side thereof to a throttle valve 13; multiple branch pipes 12 that are arranged side by side in a longitudinal direction of the surge tank 11 and respectively connected to cylinders; and a PCV chamber 15 that is provided upstream of a central part in the longitudinal direction of the surge tank 11. The intake manifold includes: a blowby gas introduction port 16g that is designed to introduce blowby gas into the PCV chamber 15; and a blowby gas exhaust port 16f that is designed to discharge the blowby gas from the PCV chamber 15 into the surge tank 11, and the blowby gas exhaust port 16f is located at a position higher than the blowby gas introduction port 16g.