Methods and systems are provided for using a crankcase vent tube pressure or flow sensor for diagnosing a location and nature of crankcase system integrity breach. The same sensor can also be used for diagnosing air filter plugging and PCV valve degradation. Use of an existing sensor to diagnose multiple engine components provides cost reduction and sensor compaction benefits.

A reciprocating machine incitides a cylinder including an internal cylinder wail, a piston movable in the cylinder between a top position and a. bottom position, the piston, comprising an upper ring pack and a lower ring pack disposed around a circumference of the piston and spaced from each other by a first distance, and a circumferential collector groove in the cylinder wall in a position that is above the lower ring pack when the piston is in the top position and that is below the upper ring pack when the piston is in the bottom position, the collector groove including at least one hole eonneciabie to a conduit for comieciion to a sump. A helical groove can also be provided in the cylinder wall.

A method and apparatus for providing constant fresh air ventilation to the engine crankcase are disclosed. The apparatus is adapted for use with an internal combustion engine having a crankcase, an intake manifold and an air input attached to the manifold. The system includes an integrated vacuum actuator connected to the intake manifold, an actuator duct positioned between the vacuum actuator and the air input, an air-from-oil separator associated with the crankcase, a separator duct and separator control valve positioned between the separator and the intake manifold, and a bypass duct and bypass control valve between the separator duct and the actuator duct. The air input comprises an initial intake pipe and an intermediate intake pipe with the intermediate intake pipe being positioned between the initial intake pipe and the intake manifold. A fresh air control pipe and regulator assembly are attached to the intermediate intake pipe.

A Positive Crankcase Ventilation (PCV) channel disconnect detection device and method is provided for an engine having a crankcase, an intake system for delivering metered air to the engine, and a PCV channel for containing PCV gas flow between the crankcase and the intake system and having a first end and a second end. The PCV channel disconnect detection device includes a detection channel that supplies unmetered air surrounding one of the ends of the PCV channel to a post-throttle portion of the intake system. The detection channel is inoperable in response to a vacuum in the post-throttle portion of the intake system if the PCV channel connection is connected. The detection channel is operable in response to the vacuum in the post-throttle portion of the intake system if the PCV channel is disconnected. The detection channels may be configured to bypass all flow restrictions in the PCV system.

Methods and systems are provided for controlling air ingestion in an engine during idle conditions. One example approach includes adjusting an opening of a common shut-off valve via an electronic controller, the common shut-off valve regulating each of motive flow through an aspirator and crankcase ventilation (CV) flow from a crankcase. As such, the common shut-off valve may be closed by the electronic controller during engine idle to cease each of the motive flow through the aspirator and the CV flow from the crankcase.

The object of the invention is to provide a cylinder head cover which comprises an integrated valve device and is easy to produce. To achieve this object, according to the invention the cylinder head cover comprises the following: a cover body which, when the cylinder head cover is mounted, is arranged on an engine block of the internal combustion engine and covers a cylinder head of the internal combustion engine; a valve device comprising a valve body and a main body for receiving the valve body, the main body of the valve device being secured to an inner face of the cover body by means of a weld joint.

An intake system of an internal combustion engine with a supercharger includes: a negative pressure control valve which is disposed in the upstream side than an intake side supercharger in an intake passage; a first external gas introduction passage which introduces a single external gas made of blow-by gas, at a part of the intake passage which is on the upstream side of the intake side supercharger and on the downstream side of the negative pressure control valve; and a fresh air introduction passage which introduces fresh air to an internal combustion engine main body from the upstream side of the negative pressure control valve.

Disclosed is an intake manifold for a vehicle with a unified flow path. The intake manifold has a plurality of branch pipes connected to intake ports of cylinders of an automotive engine, and a surge tank unit connected to the branch pipes and having an external air inlet formed at a side to receive external air, in which the surge tank unit has a unified gas inlet formed at the external air inlet so that blow-by gas an fuel evaporation gas both flows inside. Accordingly, flow resistance when external air flows inside is reduced and freezing at the blow-by gas inlet is prevented in winter. Therefore, the amount of air mixture to be supplied into the cylinders is increased, whereby the volume efficiency of the cylinders is improved and engine torque is increased.

An ejector includes: a decompression chamber in an outer pipe on an air entrance side; a throat in the outer pipe on an air exit side; a nozzle in the outer pipe on the air entrance side, the nozzle having a leading end portion placed in a decompression chamber to inject air; and a suction port in the decompression chamber to suck blow-by gas into the decompression chamber. The air injected from the nozzle generates negative pressure in the decompression chamber to suck in blow-by gas through the suction port, and the sucked gas is discharged together with air through a throat. The valve in the nozzle includes a valve seat, a valve element, and a spring to press the valve element in a direction to separate from the valve seat. The valve element is formed with a bottom-closed cavity opening toward an upstream side of an air flow.

Restrictors are disclosed that include a body defining a Venturi tube having a throat defining a junction of a converging inlet cone to a diverging outlet cone along a longitudinal axis thereof, and with the converging inlet cone and the diverging outlet cone each defining an inner passageway that transitions as a hyperbolic or parabolic function toward the throat.