Methods and systems are provided for an exhaust gas arrangement. In one example, a system comprises an air supply device arranged between a first LNT and a second LNT. The air supply device positioned to adjust an air/fuel ratio and a temperature of exhaust gas flowing to the second LNT and devices downstream thereof.

Methods and systems are provided for implementing fluid injection through a cylinder valve seat. The engine system may include a cylinder valve with a valve head mating with a valve seat when the valve is closed. The valve seat includes an injection orifice blocked by the valve head when the cylinder valve is closed and unblocked when the cylinder valve is opened.

A catalyst warming apparatus includes an air blower, a fuel feeder, and an air blowing controller. The air blower is disposed between an engine and a purification catalyst in an exhaust pipe communicating with the engine and is configured to blow air toward the purification catalyst. The fuel feeder is configured to cause the purification catalyst to retain fuel. The air blowing controller is configured to start driving the air blower at a predetermined start timing before a start of the engine.

A method, used with an internal combustion engine, of providing fresh air for regeneration of an exhaust aftertreatment device. An air intake diversion line is installed from a point between the throttle and the compressor to a point upstream of the exhaust aftertreatment device. A valve on this diversion line is normally closed. If the engine temperature is above a certain threshold and if the engine is in a high load deceleration state, the valve is opened, which diverts fresh air to the exhaust aftertreatment device. The valve is then closed after the pressure in the intake line is relieved.

A method, used with an internal combustion engine, of providing fresh air for regeneration of an exhaust aftertreatment device. An air intake diversion line is installed from a point between the throttle and the compressor to a point upstream of the exhaust aftertreatment device. A valve on this diversion line is normally closed. If the engine temperature is above a certain threshold and if the engine is in a high load deceleration state, the valve is opened, which diverts fresh air to the exhaust aftertreatment device. The valve is then closed after the pressure in the intake line is relieved.

A method and control device for correcting an output signal of an exhaust gas sensor in an exhaust gas conduit of an internal combustion engine, a secondary air delivery system for delivering air into the exhaust gas conduit being associated with the exhaust gas conduit upstream from the exhaust gas sensor in the flow direction of the exhaust gas. During a measurement of the output signal of the exhaust gas sensor, air is delivered to the exhaust gas conduit via the secondary air delivery system during a correction phase by way of which a correction of the output signal of the exhaust gas sensor is derived. In this operating mode, a defined oxygen content exists in the gas mixture surrounding said sensor, so that the output signal can be compared with reference values.

Methods and systems are provided for implementing fluid injection through a cylinder valve seat. The engine system may include a cylinder valve with a valve head mating with a valve seat when the valve is closed. The valve seat includes an injection orifice blocked by the valve head when the cylinder valve is closed and unblocked when the cylinder valve is opened.

Separation efficiency of a gas in a gas separator mounted on a vehicle is improved. The gas separation system mounted on the vehicle provided with an internal combustion engine includes the gas separator configured to separate a predetermined component in the gas under the existence of water, a first passage connected to the gas separator so as to introduce an atmosphere into the gas separator, and a second passage connecting between an exhaust passage of the internal combustion engine and the first passage so as to introduce exhaust gas of the internal combustion engine into the gas separator.

There is provided a secondary air introduction device configured to introduce air into an exhaust port provided in a cylinder head of an engine by using a negative pressure in the exhaust port. A back-flow restriction member is provided between a reed valve and the exhaust port in an air introduction passage, and includes a plate part intersecting with an extension direction of the air introduction passage. The plate part has an air passing region in which the air flowing through the air introduction passage from an air intake unit toward the exhaust port is enabled to pass therethrough and a back-flow cutoff region in which exhaust air, which flows in a direction of directly colliding with at least a valve body of the reed valve, of exhaust air flowing back through the air introduction passage from the exhaust port is cut off.

An internal combustion engine has a cylinder head having an integrated exhaust manifold which has multiple exhaust ducts; and a secondary air system for supplying ambient air that is additionally supplied through an inlet as secondary air into the exhaust manifold into the exhaust gas flow downstream from the exhaust valves of the internal combustion engine during the cold-start phase. For fresh air supply, the secondary air system has a plurality of supply ducts that connect a distributor block of the secondary air system to an exhaust duct and are arranged in the integrated exhaust manifold and each provided with a valve assembly. Each valve assembly has a blocking means in the form of a closure flap that is pivotable about a pivot axis at a distance from the center of mass of the blocking means. According to the installation position of the internal combustion engine in a motor vehicle, and owing to this eccentric arrangement of the pivot axis, the blocking means assumes a defined closed position under the influence of gravity when there is no pressure difference between the exhaust manifold and the secondary air system and opens automatically under the influence of a relative overpressure in the gas pressure on the side of the secondary air system in relation to the gas pressure on the side of the exhaust manifold.