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.

A valve for controlling a gas stream between a first side and a second side of the valve is described. A valve opening is passage for the gas stream between the first side and the second side. A valve closure with a valve plate closes the valve opening. A valve mount is arranged toward the second side and on which the valve closure is mounted. The valve closure is pretensioned in the direction of the first side to close the valve toward the second side by the valve plate. The valve plate has an opening element which can be opened toward the first side in the event of an overpressure on the second side.

A diffuser for a jet pump of a separator comprises an inlet defining a first flow area; an outlet in fluid communication with the inlet through which fluid exits the diffuser, in which a flow path extends from the inlet to the outlet, and in which the outlet defines a second flow area greater than the first flow area so that a velocity of fluid flowing through the inlet is greater than a velocity of fluid flowing through the outlet; and a communication port extending through a wall of the diffuser with an inlet in communication with an interior of the diffuser and an outlet in communication with an exterior of the diffuser, in which the communication port inlet is between the diffuser inlet and the diffuser outlet, so that contaminants separated from the fluid stream are removed through the communication port.

An internal combustion engine includes a block containing a crankshaft and a crankcase surrounding the crankshaft, a plurality of combustion chambers configured to receive an intake fluid and generate exhaust fluid, an exhaust circuit configured to direct the exhaust fluid away from the plurality of combustion chambers, an intake circuit configured to supply the intake fluid to the plurality of combustion chambers, a turbine disposed in the exhaust circuit and having a turbine shaft configured to be driven by the exhaust fluid, a crankcase ventilation circuit configured to direct crankcase fluid away from the crankcase, and a pump disposed in the crankcase ventilation circuit and having a rotor configured to be driven by the turbine shaft to propel the crankcase fluid through the crankcase ventilation circuit.

A valve cover module includes a unitary cover and carrier made of a carbon fiber composite. The unitary cover and carrier has a lower side with a peripheral edge for attaching to a cylinder head. The lower side of the unitary cover and carrier also has a series of cavities interconnected with aligned apertures defining bearing surfaces. A plurality of cam lobes is disposed in the series of cavities. Also, the valve cover module includes a camshaft rotatable on the bearing surfaces and extending through the aligned apertures to couple with the cam lobes.

Methods and systems are provided for diagnosis of oil dilution in an engine. In one example, a method may include sealing a crankcase and spinning an engine unfueled to heat and vaporize the oil in response to detection of rich engine operation. Pressure measurements at the sealed crankcase may be collected and compared to a baseline to diagnose a presence of fuel in the oil.

Positive crankcase ventilation (PCV) systems have been employed on naturally-aspirated engines for over half a century. The gases in the crankcase exit the engine into the engine intake due to the slightly elevated pressure in the crankcase. Flow is controlled via a PCV valve in a PCV duct. In pressure-charged engines, PCV flow stops when pressure in the intake exceeds that of the crankcase. Such stagnation leads to sludging and deposit formation. According to an embodiment of the disclosure, reverse flow through the system is allowed by installing a second PCV valve in parallel with the normally-provided PCV valve, with the second PCV valve allowing an opposite direction of flow. Oil separators are provided on both PCV ducts to and from the engine to remove oil from blowby gases for flow in either direction.

An engine system comprises an intake manifold including a manifold body downstream of an intake port and having a first through-aperture and a second through-apertures spaced apart from the first through-aperture on the manifold body; a positive crankcase ventilation (PCV) system including a first PCV branch and a second PCV branch communicated fluidly with the first through-aperture and the second through-aperture of the manifold body, respectively, and configured to route a blow-by gas in a crankcase to the intake manifold; and a variable valve assembly to regulate a flow passing through the first or second PCV branches.

An oil and air separator including a catch can with an inlet and an outlet thereto, the catch can adapted to remove oil from vapors entering the catch can via the inlet, and including an internal reservoir within which oil from the vapors entering the catch can may collect; and a check valve including a first end disposed within the internal reservoir, a second end, and a first fluid pathway therebetween in fluid communication with the internal reservoir, wherein vapors within the internal reservoir may exit the catch can through the first fluid pathway or a second fluid pathway including the outlet.

A sensor circuit for a positive crankcase ventilation (PCV) valve includes an electrical source, a measuring circuit, a position calculator, and a transmitter. The electrical source is configured to apply an electrical bias across a spring of the PCV valve. The electrical bias is applied between a first end of the spring and an opposite end of the spring. The measuring circuit is configured to measure a value of an electrical parameter of the spring while the electrical bias is applied. The electrical parameter indicates at least one of a voltage across the spring and a current through the spring. The position calculator is configured to calculate an inductance of the spring based on the value of the electrical parameter and calculate a position of the PCV valve based on the inductance. The transmitter is configured to output a signal that indicates the position of the PCV valve.