A control device of a vehicle capable of improving acceleration responsiveness and suppressing increase in the NOx emission amount when a required torque is increased during a steady lean operation. A target air-fuel ratio (AFCMD) is set according to an accelerator pedal operation of a driver. When the driver depresses an accelerator pedal to make an acceleration request during the lean operation, in which the AFCMD is set to a predetermined lean air-fuel ratio (AFLN), air-fuel ratio reduction control is executed to reduce the AFCMD according to the acceleration request. In the air-fuel ratio reduction control, when the AFCMD calculated according to a required torque (TRQCMD) is smaller than a limit air-fuel ratio (AFLMT), the AFCMD is set to the AFLMT, and the AFLMT is set to a value smaller than the AFLN set in a steady state of the lean operation and larger than a theoretical air-fuel ratio (AFST).

A method performed by a control unit in connection with a pre-heating process of an aftertreatment system for a combustion engine is provided. The control unit obtains a scheduled start time of the combustion engine. The control unit schedules a pre-heating of the aftertreatment system to be completed before the scheduled start time. The control unit detects a start of the combustion engine at an actual start time. In response to the detected start of the combustion engine, and using the actual and scheduled start times, the control unit determines whether the scheduled pre-heating of the aftertreatment system fulfils one or more success criteria. When the one or more success criteria are fulfilled, the control unit triggers a performance increase of the combustion engine.

An engine system includes an engine with an intake manifold and an exhaust manifold, a turbocharger including a turbine in communication with the exhaust manifold and a compressor in communication with the intake manifold, and a regulator configured to control a flow of exhaust gas through the turbine. A controller of the engine system is operably connected with the regulator and is configured to monitor an engine load and an exhaust gas temperature during operation of the engine, identify a proscribed engine NOx emissions level based on the engine load and the exhaust gas temperature and, when the proscribed engine NOx emissions level is identified, modify the flow of exhaust gas through the turbine to reduce the energy extracted from the exhaust gas by the turbine and reduce a drive power provided to the compressor, thereby reducing a flow of intake air provided to the intake manifold by the compressor.

Systems and methods for mitigating exhaust gas emissions via cylinder deactivation are provided. A system includes a controller coupled to an internal combustion engine and an electric motive device. The controller includes a processor and a memory coupled to the processor. The memory stores instruction that, when executed by the processor, cause the controller to: command the internal combustion engine to operate in a cylinder deactivation mode whereby at least one cylinder of a plurality of cylinders of the internal combustion engine is deactivated; receive a power request exceeding a current power output from the internal combustion engine; command the electric motive device to provide a supplemental power output based on the received power request; and, subsequent to commanding the electric motive device to provide the supplemental power out, activate the at least one cylinder of the plurality of cylinders of the internal combustion engine.

A method includes: initiating a low engine-out NOx (LEON) mode by controlling a component of a vehicle having an aftertreatment system to decrease an instantaneous engine-out NOx (EONOx) amount; comparing a temperature of the aftertreatment system during the LEON mode to a warm-operation threshold temperature; responsive to determining that the temperature of the aftertreatment system exceeds the warm-operation threshold temperature, disengaging the LEON mode; responsive to determining that the temperature of the aftertreatment system is below the warm-up operation threshold temperature, comparing information indicative of an operating status of the vehicle to a LEON exit threshold; and disengaging the LEON mode responsive to determining that the information indicative of the operating status of the vehicle during the LEON mode exceeds the LEON exit threshold.

Embodiments of methods and systems related to operating a mobile asset are provided. In one example, a method for operating a mobile asset includes supplying an engine with a fuel controller a first amount of a first fuel and a second amount of a second fuel and combusting the first fuel and the second fuel at a fuel combustion ratio in at least one cylinder of the engine, the first amount and the second amount being selected based on route information for a route along which the mobile asset is operable to travel and a projected exhaustion of the first fuel that does not precede a projected exhaustion of the second fuel, wherein the mobile asset is unable to operate with the second fuel alone.

A dual fuel system includes a liquid pilot fuel supply, a liquid main fuel supply, and a fuel injection apparatus. The dual fuel system further includes a fueling control unit coupled with a cylinder pressure sensor and a NOx sensor, and structured to vary, via outputting a fueling control command to a main fuel injection control valve, fuel delivery parameters each on the basis of at least one of a cylinder pressure parameter or a NOx parameter. The fueling control unit compensates via the varying fuel delivery parameters for a change to a liquid main fuel composition such as a change from a first alcohol fuel or blend to a second alcohol fuel or blend.

A three-way catalyst and an NO.sub.x adsorption catalyst are disposed in an engine exhaust passage. In a predetermined low-load engine operation area, combustion in a combustion chamber is carried out at a lean base air-fuel ratio and an air-fuel ratio in the combustion chamber is changed to a rich range at the time of discharging NO.sub.x from the NO.sub.x adsorption catalyst. In a predetermined high-load engine operation area, the air-fuel ratio in the combustion chamber is controlled to a theoretical air-fuel ratio in a feedback manner. In a predetermined middle-load engine operation area, the combustion in the combustion chamber is carried out at the base air-fuel ratio lower than the base air-fuel ratio in the low-load engine operation area and the air-fuel ratio in the combustion chamber is changed to the rich range with a period shorter than a rich period of the air-fuel ratio for discharging NO.sub.x in the low-load engine operation area.

Systems and methods for mitigating exhaust gas emissions via cylinder deactivation are provided. A system includes a controller coupled to an internal combustion engine and an electric motive device. The controller includes a processor and a memory. The memory stores instruction that, when executed by the processor, cause the controller to: receive a power request less than a current power output from the internal combustion engine; command the electric motive device to provide a supplemental power output based on the received power request; command the internal combustion engine to operate in a cylinder deactivation mode whereby at least one cylinder of a plurality of cylinders of the internal combustion engine is deactivated; responsive to determining that a power output of the internal combustion engine is substantially equivalent to the power request after commanding the internal combustion engine to operate in the cylinder deactivation mode, deactivate the electric motive device.

A method of operating an engine is provided. The method includes determining a temperature and a pressure of intake air, and a temperature and a pressure of exhaust generated by the engine. The method includes determining a work performed by the engine based at least on an engine speed of the engine, and determining heating losses of the engine. The method includes determining an enthalpy of the intake air based at least on the work, the heating losses, a heating value of a fuel used for combustion within the engine, and the temperature and the pressure of the exhaust. The method includes determining a humidity value of the intake air based on the enthalpy, temperature and pressure of the intake air and determining an amount of NOx based on the humidity value. The method further includes controlling an operation of the engine based on the determined amount of NOx.