A method of maintaining a temperature of an aftertreatment system of a vehicle, the method including: operating, by a controller, a retarder reducing driving force of a propeller shaft of the vehicle in response to a retarder operation request signal; operating, by the controller, a jake brake device which discharges a fuel-air mixture compressed in an explosion stroke of the engine to an exhaust pipe and decreases revolutions per minute (RPM) of the engine or an exhaust brake device which blocks a discharge of the exhaust gas of the engine to a rear end of the exhaust pipe and decreases the RPM of the engine, in order to remove the output error value; and controlling, by the controller, the engine so that an amount of exhaust gas introduced into the aftertreatment system is decreased.

A system includes a controller configured to perform an enable operation responsive to receiving information indicative of an enable parameter, the enable operation includes: determining a predicted downstream NOx value of an exhaust gas stream exiting a NOx storage catalyst; determining a downstream NOx value of the exhaust gas stream exiting the NOx storage catalyst; determining an error between the predicted downstream NOx value and the determined downstream NOx value; comparing the error to an error threshold; and determining that the NOx storage catalyst is in good health responsive to determining that the error does not exceed the error threshold. The controller is further configured to perform a disable operation responsive to receiving information indicative of a disable parameter, the disable operation causing a deactivation of at least a portion of the controller.

A system includes an engine adapted to output a torque, a parasitic load adapted to receive a portion of the torque from the engine, and a controller communicably coupled to the parasitic load. The controller is configured to determine an actual exhaust temperature value of an exhaust gas flow exiting the engine and a minimum fuel amount to be injected into the engine. The controller is configured to compare the actual exhaust temperature value with an exhaust temperature threshold value of the exhaust gas flow to determine a first difference between the actual exhaust temperature value and the exhaust temperature threshold value. The controller is configured to determine a target torque output of the engine based on the first difference and the minimum fuel amount. The controller is configured to cause the torque to be increased to attain the target torque output using the parasitic load.

A method for operating an internal combustion engine is provided. The method includes during a first operating condition, operating two primary cylinders and two secondary cylinders to perform combustion, the two primary and secondary cylinders arranged in an inline configuration, the two primary cylinder adjacent to one another, the two secondary cylinders adjacent to one another, and the secondary cylinders positioned 175°-185° out of phase relative to the two primary cylinders and during a second operating condition, selectively deactivating the two secondary cylinders to perform combustion in only the two primary cylinders.

A control system includes an electric heater disposed within an exhaust fluid flow pathway, and a control device for receiving at least one input selected from the group consisting of temperature readings along the exhaust fluid flow pathway, alternator power/current/voltage, battery power/current/voltage/state of charge, IAT and EAT profiles, mass flow rate of an exhaust fluid flow, NH.sub.3 slip, TCR characteristics of the heater, alternator speed, engine speed, state of aging of an aftertreatment component, state of aging of engine, aging degradation characteristics, a dosing rate and a temperature of DEF, NH.sub.3 storage condition of aftertreatment system, an ambient temperature, and combinations thereof. The control device modulates power to the heater based on the at least one input such that the heater provides different power output as a function of the at least one input and a continuously variable power output during operation of the exhaust system.

A vehicle includes an engine and a particulate filter that is situated to filter particulates from the exhaust fluid. A controller is configured to implement a sequence of particulate filter regeneration techniques including a first technique during an engine cold start condition, a second technique during a running engine idle condition, and a third technique during a driving condition. The controller is configured to determine whether particulate filter regeneration is desired, implement the first technique when particulate filter regeneration is desired, determine whether particulate filter regeneration is still desired after using the first technique, implement the second technique when regeneration is still desired after using the first technique, determine whether particulate filter regeneration is still desired after using the second technique, and implement the third technique when regeneration is still desired after using the second technique.

Provided is a diesel engine capable of regenerating a DPF even during no-load and/or light-load operation. In a DPF regeneration process, opening-degree reduction control S2 for an exhaust-air throttle valve is performed after a start condition S1 of the regeneration process of the DPF in which PM is deposited is satisfied. When exhaust air reaches a temperature equal to or higher than a predetermined after-injection permissible temperature TA, after-injection control is subsequently started S5. Post-injection control is started S7 after the exhaust air reaches a temperature equal to or higher than a predetermined post-injection permissible temperature TP by combustion of after-injection fuel. The PM deposited in the DPF is incinerated by the exhaust air increased in temperature by catalytic combustion of post-injection fuel in a valve downstream-side DOC.

In an opposed-piston engine which includes a catalytic aftertreatment device in its exhaust system an exhaust gas condition indicating a catalyst temperature of the aftertreatment device is monitored. When the catalyst temperature is near or below a light-off temperature, a catalyst light-off procedure is executed to elevate the temperature of the catalyst.

The present invention relates to a method for increased exhaust gas temperature and emission reduction at partial loads in a diesel engine, wherein said engine comprises a cylinder with a reciprocating piston, a variable compression volume (VCR), and at least one exhaust valve and at least one inlet valve, the latter being equipped with variable valve timing (WT). According to the prevailing engine power requirement, an engine control system determines when to open and close said inlet valve, and the size of said compression volume in order to achieve a sufficiently elevated exhaust gas temperature so that correct exhaust gas purification can be achieved. The method is characterized in that the cylinder pressure during the expansion stroke is managed by the engine control system by means of the VCR and VVT functions, such that said pressure reaches atmospheric or sub atmospheric levels at or before bottom dead centre, at engine loads at or below 25% of the maximum engine load, whereby the inlet valve is opened to allow air to mix with the combustion gases. The invention also relates to a corresponding device and a diesel engine comprising said device.

Provided are methods for operating an internal combustion engine system including: an internal combustion engine provided with a plurality of cylinders, each of which being provided with an air inlet valve and an exhaust gas valve; a fuel supply system configured to supply fuel to the cylinders; an air intake system and an exhaust gas system; a turbocharging arrangement comprising an intake air compressor arranged in the air intake system and an exhaust gas turbine arranged in the exhaust gas system, wherein the intake air compressor is operatively connected to the exhaust gas turbine; a controllable gas feeding device arranged in the air intake system downstream the intake air compressor; an exhaust gas aftertreatment system arranged downstream the exhaust gas turbine; and a wastegate.