Abstract: Methods and systems are provided for re-combustion of exhaust in a cylinder of a multi-cylinder engine in order to increase the temperature of the exhaust for enhancing catalytic conversion within the multi-cylinder engine. In one example, a method may include expelling combusted gases from the cylinder into an intake manifold via an intake valve during an exhaust stroke, in order to rebreathe in the combusted gases from the intake manifold via the intake valve in a subsequent intake stroke.

Abstract: Methods and systems are provided for re-combustion of exhaust in a cylinder of a multi-cylinder engine in order to increase the temperature of the exhaust for enhancing catalytic conversion within the multi-cylinder engine. In one example, a method may include expelling combusted gases from the cylinder into an intake manifold via an intake valve during an exhaust stroke, in order to rebreathe in the combusted gases from the intake manifold via the intake valve in a subsequent intake stroke.

Abstract: Methods and systems are provided for re-combustion of exhaust in a cylinder of a multi-cylinder engine in order to increase the temperature of the exhaust for enhancing catalytic conversion within the multi-cylinder engine. In one example, a method may include expelling combusted gases from the cylinder into an intake manifold via an intake valve during an exhaust stroke, in order to rebreathe in the combusted gases from the intake manifold via the intake valve in a subsequent intake stroke.

Abstract: Methods and systems are provided for re-combustion of exhaust in a cylinder of a multi-cylinder engine in order to increase the temperature of the exhaust for enhancing catalytic conversion within the multi-cylinder engine. In one example, a method may include expelling combusted gases from the cylinder into an intake manifold via an intake valve during an exhaust stroke, in order to rebreathe in the combusted gases from the intake manifold via the intake valve in a subsequent intake stroke.

Abstract: Methods and systems are provided for expediting exhaust catalyst light-off prior to an anticipated engine cold-start event. In one example, a method may include, in anticipation of an engine cold-start, preemptively operating an electric booster and routing compressed air to the catalyst to increase a temperature of the exhaust catalyst while maintaining the engine inactive.

Abstract: Methods and systems are provided for a turbocharger. In one example, a method may include flowing bleed air to control a catalyst temperature. The bleed air is directed from a bleed port of a compressor of an engine system.

Abstract: Methods and systems are provided for cylinder deactivation to reduce tailpipe emissions and increase exhaust temperature. In one example, a method may include operating a first set of cylinders in a first combustion cycle over modified eight strokes and a second set of cylinders in a second combustion cycle over modified four strokes. Each cylinder in the first set of cylinders may be selectively deactivated via a variable displacement engine (VDE) mechanism while each cylinder in the second set of cylinders may be selectively deactivated via an active decompression technology (ADT) mechanism.

Abstract: Methods and systems are provided for a turbocharger. In one example, a method may include bypassing exhaust gases flowing to the turbocharger in response to a catalyst temperature being less than a threshold temperature. The bypassing includes opening a bypass valve and adjusting a position of one or more turbine nozzle vanes.

Abstract: Methods and systems are provided for a turbocharger. In one example, a method may include bypassing exhaust gases flowing to the turbocharger in response to a catalyst temperature being less than a threshold temperature. The bypassing includes opening a bypass valve and adjusting a position of one or more turbine nozzle vanes.

Abstract: Methods and systems for increasing exhaust gas temperatures of an engine are described. In one example, engine exhaust gas temperatures may be increased via deactivating cylinders and flowing exhaust gases through deactivated cylinder. Engine pumping losses may be reduced via the exhaust gases that flow through the deactivated cylinder so as to reduce engine fuel consumption while heating an exhaust gas after treatment device.

Abstract: Methods and systems for maintaining a temperature of catalyst above a threshold temperature during vehicle braking and coasting is described. In one example, engine pumping work may be increased without increasing flow of cool fresh air through the engine's exhaust system to provide a desired level of engine braking. The net air flow through the engine may be reduced via activating a decompression actuator.

Abstract: Methods and systems for maintaining a temperature of catalyst above a threshold temperature during vehicle braking and coasting is described. In one example, engine pumping work may be increased without increasing flow of cool fresh air through the engine's exhaust system to provide a desired level of engine braking. The net air flow through the engine may be reduced via activating a decompression actuator.

Abstract: Methods and systems for increasing exhaust gas temperatures of an engine are described. In one example, engine exhaust gas temperatures may be increased via deactivating cylinders and flowing exhaust gases through deactivated cylinder. Engine pumping losses may be reduced via the exhaust gases that flow through the deactivated cylinder so as to reduce engine fuel consumption while heating an exhaust gas after treatment device.

Abstract: Systems and methods are provided for using an electric machine as a generator to control boost during an engine cold start. In one example, a method may include receiving a request to increase an engine load during the engine cold start, determining an available capacity of a battery, operating the electric machine as a generator to increase the engine load with an electrical load, and responsive to the available capacity of the battery being less than a charge threshold, charging the battery with the electrical load while generating an increased boost pressure with an electric boosting device by powering the electric boosting device via the battery, and coordinating an amount of the increased boost pressure to compensate the electrical load. By increasing the engine load during the engine cold start, an exhaust gas temperature may be increased to achieve catalyst light-off.

Abstract: Systems and methods are provided for using an electric machine as a generator to control boost during an engine cold start. In one example, a method may include receiving a request to increase an engine load during the engine cold start, determining an available capacity of a battery, operating the electric machine as a generator to increase the engine load with an electrical load, and responsive to the available capacity of the battery being less than a charge threshold, charging the battery with the electrical load while generating an increased boost pressure with an electric boosting device by powering the electric boosting device via the battery, and coordinating an amount of the increased boost pressure to compensate the electrical load. By increasing the engine load during the engine cold start, an exhaust gas temperature may be increased to achieve catalyst light-off.

Abstract: A method and apparatus to predict and enable control of misfire that influences combustion cyclic variation and COV of IMEP in spark-ignited (SI) engine. The method includes obtaining engine data and determining temperature and pressure within a cylinder in response to engine data; determining crank angle resolved flame velocity evolution based on the engine data; comparing the crank angle resolved flame velocity to predetermined turbulent combustion regime data to determine a misfire occurrence; and updating a misfire occurrence indicator and outputting a control signal when the misfire occurrence indicator is greater than a predetermined limit, the control signal being capable of adjusting any engine actuators, such as external ignition source, of the spark-ignited engine on a cycle to cycle basis. The method and apparatus further includes correlating the crank angle resolved flame velocity to combustion phasing when the misfire occurrence indicator is less than the predetermined limit.

Abstract: A method and apparatus to predict and enable control of misfire that influences combustion cyclic variation and COV of IMEP in spark-ignited (SI) engine. The method includes obtaining engine data and determining temperature and pressure within a cylinder in response to engine data; determining crank angle resolved flame velocity evolution based on the engine data; comparing the crank angle resolved flame velocity to predetermined turbulent combustion regime data to determine a misfire occurrence; and updating a misfire occurrence indicator and outputting a control signal when the misfire occurrence indicator is greater than a predetermined limit, the control signal being capable of adjusting any engine actuators, such as external ignition source, of the spark-ignited engine on a cycle to cycle basis. The method and apparatus further includes correlating the crank angle resolved flame velocity to combustion phasing when the misfire occurrence indicator is less than the predetermined limit.