Abstract: Methods and systems are provided for reducing emissions during an engine cold start. In one example, a method may include, during emission control device heating, injecting heated air into an exhaust runner of each cylinder of the engine during an exhaust stroke of the corresponding cylinder, after a blowdown exhaust pulse. In this way, an amount of hydrocarbons in feedgas provided to the emission control device prior to the emission control device reaching its light-off temperature may be reduced.

Abstract: Methods and systems are provided for providing compression release during a stop/start event in an engine. In one example, a method includes: responsive to a request for a stop/start event in an engine with a continuously variable valve lift (CVVL) system including a compression release hydraulic valve actuator coupled to a valve of a first cylinder, determining a desired stop position of the engine; and prior to restarting the engine during the stop/start event, adjusting the compression release hydraulic valve actuator to open the valve during a compression stroke of the first cylinder. In this way, an amount of torque used to restart the engine may be reduced.

Abstract: Methods and systems are provided for reducing emissions during an engine cold start. In one example, a method may include, during emission control device heating, injecting heated air into an exhaust runner of each cylinder of the engine during an exhaust stroke of the corresponding cylinder, after a blowdown exhaust pulse. In this way, an amount of hydrocarbons in feedgas provided to the emission control device prior to the emission control device reaching its light-off temperature may be reduced.

Abstract: Methods and systems are provided for providing compression release during a stop/start event in an engine. In one example, a method includes: responsive to a request for a stop/start event in an engine with a continuously variable valve lift (CVVL) system including a compression release hydraulic valve actuator coupled to a valve of a first cylinder, determining a desired stop position of the engine; and prior to restarting the engine during the stop/start event, adjusting the compression release hydraulic valve actuator to open the valve during a compression stroke of the first cylinder. In this way, an amount of torque used to restart the engine may be reduced.

Abstract: Methods and system for providing heat to a vehicle are presented. In one example, a refrigerant loop is operated to heat a passenger cabin via heat generated by a compressor and heat generated by a resistive heating element. The heat that is generated by the compressor and the heat that is generated by the resistive heating element is transferred to a refrigerant before it is transferred to the passenger cabin.

Abstract: Methods and systems are provided for restarting an engine following an engine idle-stop. In one example, a method may include upon receiving an engine restart request during an engine idle-stop, initiating combustion in a selected cylinder and based on a predicted time of attainment of peak pressure in the cylinder, activating a starter motor.

Abstract: A method for starting an engine is disclosed. The method may adjust exhaust valve opening timing of one or more cylinders during a first cycle of an engine since a most recent engine stop to reduce engine cranking work. The method may adjust exhaust valve timing if the engine is directly started or started via an electric machine.

Abstract: Methods and system for providing heat to a vehicle are presented. In one example, a refrigerant loop is operated to heat a passenger cabin via heat generated by a compressor and heat generated by a resistive heating element. The heat that is generated by the compressor and the heat that is generated by the resistive heating element is transferred to a refrigerant before it is transferred to the passenger cabin.

Abstract: Methods and systems are provided for a pre-chamber ignition system. In one example, a pre-chamber ignition system may include a pre-chamber extending into a combustion chamber, a piston protrusion shaped to fit through a bottom aperture of the pre-chamber, and a plurality of orifices formed by sidewall of the pre-chamber. A method for the pre-chamber ignition system includes adjusting spark timing within the pre-chamber and pressing the protrusion into the pre-chamber to ignite air/fuel within a main chamber.

Abstract: Methods and systems are provided for purging a pre-chamber. In one example, a system is provided with a combustion chamber formed by a cylinder head coupled to a cylinder block and a pre-chamber in fluidic communication with the combustion chamber. The system is also provided with a purge port coupled to the pre-chamber and structured to flow purge air into the pre-chamber, where the flow of the purge air is driven by operation a purge pump and a piston disposed within the combustion chamber.

Abstract: Methods and systems are provided for particulate matter control in an engine configured for skip-fire operation. A cylinder pattern selected for selective cylinder deactivation, including a total number of deactivated/active cylinders as well as individual deactivated cylinder identities, may be adjusted based on an engine soot load, or a parameter indicative of engine soot load such as engine coolant temperature. In addition, reactivated engine cylinders may be transiently operated with split fuel injection to raise combustion surface temperatures.

Abstract: Methods and systems are provided for flowing exhaust through a second cooler, arranged downstream of a first cooler and upstream of an intake in an exhaust gas recirculation passage, and extracting condensate for water injection from condensate in cooled exhaust gas exiting the second cooler. In one example, a method may include adjusting the amount of exhaust gas flowing through the second cooler based on an amount of water stored at a water storage tank of a water injection system and engine operating conditions. Further, the method may include selectively flowing exhaust gas from the second cooler to a location upstream or downstream of a compressor in response to engine operating conditions.

Abstract: Systems and methods are provided for engine systems including a multiple tap aspirator with a throat tap and a diffuser tap. Suction passages coupled to the throat and diffuser taps, respectively, may fluidly communicate via a leak passage with a flow restriction. During conditions where the pressure at a suction flow source of the diffuser tap is less than the pressure at the diffuser tap, backflow from the diffuser tap may travel through the leak passage into the throat tap.

Abstract: Methods and systems are provided for purging a pre-chamber. In one example, a system is provided with a combustion chamber formed by a cylinder head coupled to a cylinder block and a pre-chamber in fluidic communication with the combustion chamber. The system is also provided with a purge port coupled to the pre-chamber and structured to flow purge air into the pre-chamber, where the flow of the purge air is driven by operation a purge pump and a piston disposed within the combustion chamber.

Abstract: Methods and systems are provided for enhancing turbocharger performance for a boosted engine system configured to operate with a pattern of deactivated cylinders. In one example, a method may include, in response to a demand for boost, operating with a cylinder pattern based on boost demand and turbocharger configuration. The specific pattern may depend on the pattern constraints imposed by engine load and NVH metrics.

Abstract: Methods and systems are provided to improve engine temperature control. Cylinders scheduled for deactivation may have their exhaust retained in the cylinder by holding an exhaust valve closed on the preceding firing cycle. In this way soot emissions on reactivation are reduced.

Abstract: Methods and systems are provided for providing vacuum to a brake booster via an aspirator system. In one example, a system may include an aspirator system fluidly coupled with a brake booster with no intervening components located therebetween.

Abstract: Methods and systems are provided for a pre-chamber ignition system. In one example, a pre-chamber ignition system may include a pre-chamber extending into a combustion chamber, a piston protrusion shaped to fit through a bottom aperture of the pre-chamber, and a plurality of orifices formed by sidewall of the pre-chamber. A method for the pre-chamber ignition system includes adjusting spark timing within the pre-chamber and pressing the protrusion into the pre-chamber to ignite air/fuel within a main chamber.

Abstract: Methods and systems are provided for flowing exhaust through a second cooler, arranged downstream of a first cooler and upstream of an intake in an exhaust gas recirculation passage, and extracting condensate for water injection from condensate in cooled exhaust gas exiting the second cooler. In one example, a method may include adjusting the amount of exhaust gas flowing through the second cooler based on an amount of water stored at a water storage tank of a water injection system and engine operating conditions. Further, the method may include selectively flowing exhaust gas from the second cooler to a location upstream or downstream of a compressor in response to engine operating conditions.

Abstract: Methods and systems are provided for enhancing turbocharger performance for a boosted engine system configured to operate with a pattern of deactivated cylinders. In one example, a method may include, in response to a demand for boost, operating with a cylinder pattern based on boost demand and turbocharger configuration. The specific pattern may depend on the pattern constraints imposed by engine load and NVH metrics.