Methods and systems are provided for a low temperature NOx adsorber (LTNA). In one example, a method includes initiating a desulfation of an LTNA responsive to an estimated sulfur exposure exceeding a threshold, the desulfation including heating the LTNA to a first threshold temperature while maintaining an exhaust oxygen level above a threshold level throughout the entire desulfation.

This invention provides a method to clean the inside surfaces of an engine and its exhaust after-treatment system each time the engine is shut down. This cleaning is accomplished without disassembly of the engine and without involvement of the engine's operator. This cleaning includes the combustion chamber, valves, intake and exhaust ports, particulate filters, catalytic after-treatment processes, and exhaust piping. This is accomplished by leaving the shut down engine and its exhaust after-treatment systems in an oxygen rich atmosphere where oxidation of the hydrocarbons on the inside surfaces continues.

This invention provides a method to clean the inside surfaces of an exhaust after-treatment system each time the engine is shut down. This cleaning is accomplished without disassembly of the engine and without involvement of the engine's operator. This cleaning includes the exhaust ports, particulate filters, catalytic after-treatment processes, and exhaust conduits. This is accomplished by leaving the exhaust after-treatment systems in an oxygen rich atmosphere, with the engine shut down, where oxidation of the hydrocarbons on the inside surfaces continues.

A method for operating an internal combustion engine includes combusting fuel and air within a combustion chamber of an internal combustion engine, thereby forming an exhaust gas, passing the exhaust gas out of the combustion chamber, and performing a startup procedure, the startup procedure including passing the exhaust gas from the combustion chamber through a first aftertreatment system to a pollutant capture unit, capturing criteria pollutants of the exhaust gas with the pollutant capture unit, and heating the first aftertreatment system to a first activation temperature. Subsequent to heating the first aftertreatment system to the first activation temperature a secondary procedure is performed including passing the exhaust gas from the combustion chamber directly to a second aftertreatment system bypassing the pollutant capture unit to heat the second aftertreatment system to a second activation temperature. Subsequently, exhaust gas is passed through the pollutant capture unit to desorb captured criteria pollutants.

A method for regenerating a particulate filter in an exhaust system of an internal combustion engine, wherein it is thereby provided that the quantity of overrun air in the overrun operation of the combustion engine be adapted to the air required for oxidizing the soot trapped in the particulate filter to achieve a rapid and efficient regeneration of the particulate filter, and it is provided that a throttle valve be opened in overrun operation to an extent that allows a maximum permissible soot conversion without risking thermal damage to the particulate filter.

An ECU 10 for controlling execution of forced regeneration that removes PM deposited on a DPF by increasing a temperature of the DPF in an exhaust gas treatment device of a diesel engine including a DOC disposed in an exhaust passage and the DPF disposed downstream of the DOC includes: a determination unit 102 for determining whether an injection start condition corresponding to a remaining SOF deposition amount on the DOC is satisfied after the forced regeneration starts and after an upstream temperature of the DOC reaches a predetermined temperature; and an injection execution unit 104 for starting late-post injection of fuel to the DOC when the injection start condition is satisfied.

A method for operating an internal combustion engine includes combusting a fuel and air mixture within a combustion chamber of an internal combustion engine, thereby forming an exhaust gas, passing the exhaust gas out of the combustion chamber, performing a startup procedure, the startup procedure including passing the exhaust gas from the combustion chamber to a storage unit, capturing criteria pollutants of the exhaust gas with the storage unit, passing the exhaust gas from the storage unit to an aftertreatment system, heating the aftertreatment system to an activation temperature with the exhaust gas from the storage unit, and subsequent to heating the aftertreatment system to the activation temperature, performing a secondary procedure, the secondary procedure including passing the exhaust gas from the combustion chamber to the aftertreatment system thereby forming a treated exhaust gas, and passing the treated exhaust gas to the storage unit.

In a control system for an internal combustion engine which stops the rotation of an internal combustion engine by applying a counter torque thereto, the generation of noise or vibration accompanying the stop of rotation of the internal combustion engine is suppressed as much as possible. In the control system provided with a controller being adapted to stop the rotation of the internal combustion engine by carrying out forced stop processing in which the counter torque is inputted, in cases where the forced stop processing is carried out after the completion of the execution of specific motoring processing, the controller makes the counter torque at a certain timing before the counter torque becomes a predetermined torque after the start of the execution of the forced stop processing smaller than in the case where the forced stop processing is carried out without carrying out the specific motoring processing.

A method for operating a petrol engine, in which air is introduced into an exhaust tract through which exhaust gas from the petrol engine can flow, bypassing the petrol engine, includes introducing the air into the exhaust tract at a point arranged downstream of a first three-way catalytic converter arranged in the exhaust tract and upstream of a second three-way catalytic converter arranged in the exhaust tract downstream of the first three-way catalytic converter, while the petrol engine is operated with a sub-stoichiometric combustion air ratio, where a desulphurization of the second three-way catalytic converter is effected.

An object of the disclosure is to prevent the sensing accuracy of an exhaust gas sensor from being deteriorated by the effect of electromagnetic waves in an exhaust gas purification system for an internal combustion engine that is configured to apply electromagnetic waves to the exhaust gas purification device provided in an exhaust passage of the internal combustion engine. The disclosure is applied to an exhaust gas purification system for an internal combustion engine including an exhaust gas sensor located within the range of radiation of electromagnetic waves from a radiating device that radiates electromagnetic waves of a specific frequency to an exhaust gas purification device. The system suspends the radiation of electromagnetic waves from the radiating device during a sampling period in which sampling of the output value of the exhaust gas sensor is performed, even when a specific condition for performing the radiation is met.