Based on an exhaust gas temperature on an upstream side acquired by an upstream temperature acquisition device, in performing control of supplying an unburned fuel to an oxidation catalyst device in a case where the exhaust gas temperature on the upstream side is lower than a low temperature, a control device performs control of adjusting at least one of an injection timing of a cylinder injection valve and opening-closing timing of an exhaust valve at least one of before and after the supplying control; raising a temperature of the exhaust gas that substantially free of unburned fuel discharged from the exhaust valve to be higher than the low temperature; and warming the oxidation catalyst device until a predetermined warming period has passed.

A first temperature which is a temperature of exhaust gas which has passed through an exhaust gas purification treatment device is detected during supply of urea water from a urea water supply device, and a second temperature which is a temperature of exhaust gas which has passed through a second exhaust gas purification treatment device in a state where an engine in the same operating state as when the first temperature is detected and the supply of the urea water from the urea water supply device is stopped is calculated from preset data. Further, an ammonia calorific value which is an amount of heat generated in an ammonia slip catalyst device by oxidation of ammonia is calculated based on the first temperature and the second temperature, and an ammonia slip amount from the selective reduction catalyst device is calculated based on the ammonia calorific value.

A first temperature which is a temperature of exhaust gas which has passed through an exhaust gas purification treatment device is detected during supply of urea water from a urea water supply device, and a second temperature which is a temperature of exhaust gas which has passed through a second exhaust gas purification treatment device in a state where an engine in the same operating state as when the first temperature is detected and the supply of the urea water from the urea water supply device is stopped is calculated from preset data. Further, an ammonia calorific value which is an amount of heat generated in an ammonia slip catalyst device by oxidation of ammonia is calculated based on the first temperature and the second temperature, and an ammonia slip amount from the selective reduction catalyst device is calculated based on the ammonia calorific value.

Methods and systems are provided for an aftertreatment system arranged in a vehicle underbody downstream of close-coupled aftertreatment devices, the aftertreatment system including a first aftertreatment device and a second aftertreatment device adjacent one another. In one example, the first aftertreatment device is a hydrocarbon trap and the second aftertreatment device is a three-way catalyst.

Methods and systems are provided for an aftertreatment system arranged in a vehicle underbody downstream of close-coupled aftertreatment devices, the aftertreatment system including a first aftertreatment device and a second aftertreatment device adjacent one another. In one example, the first aftertreatment device is a hydrocarbon trap and the second aftertreatment device is a three-way catalyst.

A method is presented for regulating a filling of an exhaust gas component reservoir of a catalytic converter in the exhaust of an internal combustion engine. Using a first catalytic converter model, an actual fill level of the exhaust gas component reservoir is ascertained. An aging state of the catalytic converter is determined; and a set of model parameters of the first catalytic converter model is allocated to the aging state; the individual model parameters being ascertained by interpolation from basic values of model parameters, the basic values having been determined for at least two different aging states of a catalytic converter of identical design.

A method is presented for regulating a filling of an exhaust gas component reservoir of a catalytic converter in the exhaust of an internal combustion engine. Using a first catalytic converter model, an actual fill level of the exhaust gas component reservoir is ascertained. An aging state of the catalytic converter is determined; and a set of model parameters of the first catalytic converter model is allocated to the aging state; the individual model parameters being ascertained by interpolation from basic values of model parameters, the basic values having been determined for at least two different aging states of a catalytic converter of identical design.

There is provided the diagnostic device for a sensor which is arranged in an exhaust passage of an internal combustion engine and detects a particulate matter amount in exhaust, the diagnostic device including a time-rate-of-change calculation unit which calculates a time rate of change of the particulate matter amount detected by the sensor during a period in which a fuel injection amount of the internal combustion engine is equal to or less than a predetermined injection amount threshold, and an abnormality determination unit which determines an abnormality of the sensor based on the time rate of change of the particulate matter amount calculated by the time-rate-of-change calculation unit.

There is provided the diagnostic device for a sensor which is arranged in an exhaust passage of an internal combustion engine and detects a particulate matter amount in exhaust, the diagnostic device including a time-rate-of-change calculation unit which calculates a time rate of change of the particulate matter amount detected by the sensor during a period in which a fuel injection amount of the internal combustion engine is equal to or less than a predetermined injection amount threshold, and an abnormality determination unit which determines an abnormality of the sensor based on the time rate of change of the particulate matter amount calculated by the time-rate-of-change calculation unit.

An exhaust gas purification device includes an exhaust gas discharge unit having an exhaust gas passage, and a plurality of smoke purifying units. Each smoke purifying unit includes a smoke purifying module disposed outside of the exhaust gas discharge unit and including an elongated smoke purifying holder defining a channel, and at least one water spray pipe for spraying water into the channel. An exhaust gas capture module includes a first exhaust gas capture pipe communicating the exhaust gas passage with the channel and having a first smoke trap extending into the exhaust gas passage.