An exhaust treatment system comprising: a first dosage device, arranged to supply a first additive into said exhaust stream; a first reduction catalyst device, downstream of said first dosage device arranged for reduction of nitrogen oxides in said exhaust stream through the use of said first additive; a particulate filter, at least partly comprising a catalytically oxidizing coating, which is downstream of said first reduction catalyst device to catch soot particles, and to oxidize one or several of nitrogen oxide and incompletely oxidized carbon compounds in said exhaust stream; a second dosage device, downstream of said particulate filter to supply a second additive into said exhaust stream; and a second reduction catalyst device, downstream of said second dosage device for a reduction of nitrogen oxides in said exhaust stream, with the use of at least one of said first and said second additive.

A controller for an engine includes processing circuitry configured to perform fuel cut-off for regenerating the filter by burning fine particulate matter collected in the filter. The processing circuitry is configured to perform an interruption process for interrupting the fuel cut-off in a case in which warming of the passenger compartment is requested when the fuel cut-off is being performed and an engine coolant temperature, which is a temperature of the engine coolant, becomes lower than or equal to a predetermined temperature after the fuel cut-off is started.

An internal combustion engine system includes a control system with a monitoring mechanism producing data of engine operating state within a BMEP/speed envelope, and an electronic control unit structured to output a control command to vary at least one of a fuel delivery property or an air delivery property in the engine based on the data. Outputting the control command switches the engine between or among combustion modes that each satisfy different calibration criteria for optimizing aftertreatment function.

Methods and systems are provided for improving combustion events during cold-starts of a vehicle engine, where the cold-start events include start/stop events. In one example, a method comprises spinning the engine in a reverse direction in response to an engine pull-down event where a temperature of an intake manifold of the engine is below a threshold, to heat the intake manifold by drawing exhaust system heat to the intake manifold. In this way, combustion may be improved in response to requests to start the engine, which may reduce undesired emissions and which may improve fuel economy.

A vehicle includes an internal combustion engine including an exhaust passage, a catalyst provided in the exhaust passage, and an electronic control unit. When the engine stop condition is established, the electronic control unit stops fuel injection and increases a catalyst inflow oxygen amount that is an amount of oxygen flowing into the catalyst by a specified oxygen increase amount. The engine stop condition is a condition for stopping operation of the internal combustion engine. The specified oxygen increase amount is larger than an increased part of the catalyst inflow oxygen amount that is increased by the stop of the fuel injection.

An exhaust gas purification system capable of preventing clogging of a reducing agent injection valve due to solidified urea aqueous solution to prevent a decrease in the exhaust gas purification efficiency of an internal-combustion engine. The exhaust gas purification system includes a diesel particulate filter, a reducing agent injection valve and an SCR catalyst in this order from the exhaust upstream side. A condition satisfaction determination section determines whether or not urea aqueous solution is likely to be solidified when detecting that an ignition switch is turned off, and an internal-combustion engine stop prevention section prevents the internal-combustion engine from being stopped, based on a determination by the condition satisfaction determination section.

The deterioration of an exhaust gas purification catalyst is suppressed as ranch as possible. An exhaust gas purification system for an internal combustion engine comprising: a throttle valve; a turbocharger; an exhaust gas purification catalyst; a bypass passage; a turbo bypass valve (TBV); and a controller. The controller is configured to carry out fuel out processing and deterioration suppression control. In the deterioration suppression control, when a temperature of the exhaust gas purification catalyst is equal to or higher than a predetermined temperature in the course of the execution of the fuel cut processing, the degree of opening of the TBV becomes smaller, and the degree of opening of the throttle valve becomes larger, than when the temperature of the exhaust gas purification catalyst is lower than the predetermined temperature in the course of the execution of the fuel cut processing.

Operation of the direct-injection internal combustion engine includes executing a particulate filter service routine in response to a regeneration command, wherein the particulate filter service routine includes a warm-up phase and a steady-state phase. The service routine includes determining a first temperature in the exhaust gas feedstream upstream of the oxidation catalyst and a second temperature in the exhaust gas feedstream downstream of the oxidation catalyst and upstream of the particulate filter, and determining an exhaust gas flowrate and a soot level in the particulate filter. A preferred warm-up temperature gradient in the particulate filter is determined based upon the exhaust gas flowrate and the soot level. The warm-up phase of the particulate filter service routine is determined based upon the preferred warm-up temperature gradient. Operation of the engine is controlled to achieve the preferred warm-up temperature gradient in the particulate filter during the warm-up phase.

A twin charged engine is provided comprising a catalytic converter; a first compressor which, when operated, increases engine load; a second compressor which extracts energy from the exhaust gases to increase the overall engine efficiency; and a controller configured to operate one of at least two modes. A first mode is a standard operating mode in which the system is configured to optimise the efficiency of running of the engine. A second mode is for use under special conditions.

A method for controlling an externally excited electric machine to boost regeneration of a NOx storage catalyst which is part of an assembly made up of an internal combustion engine, the externally excited electric machine which is connected to the internal combustion engine in a manner allowing the transmission of torque and which has a rotor including a rotor winding and a stator, and the NOx storage catalyst which is disposed in an exhaust-system branch downstream of the internal combustion engine, the rotor winding of the electric machine being energized with a preexcitation current as a function of an operating state of the NOx storage catalyst.