The objective of the present invention is to provide a control device for an internal combustion engine that is able to provide a more stable combustion state by suitably setting the amount of recirculated exhaust gas. The present invention is an internal combustion engine control device equipped with air cylinders and an EGR mechanism that returns exhaust gas emitted from the air cylinders to the intake side of the air cylinders, and is characterized by being equipped with an EGR control unit that controls the EGR flow volume of the EGR mechanism, and a humidity detection means that directly or indirectly detects the humidity of outside air supplied to the air cylinders, with the EGR control unit calculating the moisture amount in the outside air and the moisture amount in the recirculated exhaust gas, and controlling the EGR mechanism on the basis of: a stable combustion limit air cylinder mass, which is set in accordance with the combustion state in the air cylinders; the mass of the air introduced into the air cylinders; the mass of the fuel; and the moisture amounts.

An exhaust gas purification system comprises an exhaust gas purification device which is arranged in an exhaust gas route of an engine, renewing devices for burning and removing a particulate matter within the exhaust gas purification device, renewal advance notifying means which is actuated in the case that a clogged state of the exhaust gas purification device becomes equal to or more than a prescribed level, and renewal informing means which informs of a fact that the renewing devices are under operation. The renewal advance notifying means is actuated before actuating the renewing devices.

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.

A vehicle includes a power generation device including a multi-cylinder engine, the power generation device being configured to output drive power to wheels, an exhaust gas control apparatus including a catalyst for removing exhaust gas from the multi-cylinder engine, and a control device configured to execute catalyst temperature increase control for stopping fuel supply to at least one cylinder and supplying fuel to remaining cylinders in a case where a temperature increase of the catalyst is requested during a load operation of the multi-cylinder engine, execute control such that the power generation device supplements insufficient drive power due to the execution of the catalyst temperature increase control, and change the cylinder, to which the fuel supply is stopped, according to a stop frequency of the fuel supply or an elapsed time from a start of the stop of the fuel supply during the execution of the catalyst temperature increase control.

Methods and systems are provided for providing secondary air to an exhaust system during catalyst warm-up. In one example, a method may include, responsive to a cold start of an engine: operating the engine with a number of unfired cylinders and a remaining number of fired cylinders each engine cycle, and adjusting exhaust mixing by adjusting an exhaust valve parameter of at least one unfired cylinder of the number of unfired cylinders. In this way, the unfired cylinders may provide the secondary air as well as increased mixing of the secondary air with burned exhaust gas from fired cylinders, thus increasing exotherm production in the exhaust system to increase a temperature of the catalyst.

When a temperature increasing process is performed, a CPU sets a target temperature of a catalyst to be lower when a coolant temperature is low than when the coolant temperature is high. The CPU decreases an increase coefficient of fuel in the temperature increasing process when a value obtained by subtracting an estimated value of a temperature of the catalyst from the target temperature is equal to or less than a first prescribed value.

Provided are a method and an ICE system, including an internal combustion engine including a first and a second set of cylinders. A first and a second EGR valve control flow of exhaust gas from the cylinders to an EGR conduit. A controller controls the closing of the second EGR valve, thereby preventing flow of exhaust gas from the second set of cylinders to the EGR conduit. The second EGR valve is upstream of a turbine. The controller is configured to activate a fuel injector for late post injection of fuel into the second set of cylinders when the second EGR valve is closed, so that at least a part of the fuel that exits the second set of cylinders is uncombusted. An exhaust gas aftertreatment system receives and treats exhaust gas which is not recirculated in the EGR conduit, and includes an oxidation catalyst for combustion.

Systems and methods for controlling a gasoline urea selective catalytic reductant catalyst are described. In one example, an observer is provided that corrects an estimate of an amount of NH.sub.3 that is stored in a SCR. The amount of NH.sub.3 that is stored in the SCR is a basis for generating additional NH.sub.3 or ceasing generation of NH.sub.3.

Systems and methods for heating an exhaust after treatment device and producing smooth engine torque output are described. In one example, exhaust valve opening time is adjusted to compensate for additional torque that may be generated via combusting rich air-fuel mixtures in cylinders. In addition, intake valve lift may be adjusted to compensate for additional torque that may be generated via combusting rich air-fuel mixtures in cylinders.

The invention relates to a method to heat exhaust gases to a selected specific temperature by fuel injection control in an internal combustion engine (112), which engine comprises a control unit (115) registering the currently requested load and determining a required fuel amount in response to the requested load. The method involves registering low load operation of the internal combustion engine; registering an input from at least one exhaust after-treatment system (121) sensor indicating a detected condition; determining an exhaust temperature requirement for the detected condition and calculating a target exhaust temperature; selecting a group of cylinders to be regulated for achieving the target exhaust temperature; calculating a ratio for desired 1.sup.st and 2.sup.nd fuel amounts to be injected alternately in consecutive induction strokes for the selected group of cylinders to achieve the target exhaust temperature; wherein the ratio defines an offset between an increased 1.sup.st fuel amount to be injected in a cylinder of the selected group of cylinders for every second induction stroke, and a reduced 2.sup.nd fuel amount to be injected for the intermediate induction strokes.