A method for predicting urea crystal build-up in an engine system when operating according to an intended drive cycle. The method includes providing data representing engine operational conditions for the internal combustion engine during the intended drive cycle, wherein the data comprises values for at least engine speed and engine torque distributed over a time period representing the intended drive cycle; determining values and time variation for at least one exhaust parameter during the time period of the intended drive cycle when the engine system is operated according to the engine operational condition data; providing a reference relation between values and time variation for the at least one exhaust parameter and an expected urea crystal build-up in the engine system when operating the engine system at different engine operational conditions, predicting urea crystal build-up in the engine system when operating according to the intended drive cycle by comparing the determined values and time variation for the at least one exhaust parameter with the reference relation.

A method detects a manipulation of an exhaust gas system, in which measured values are sent to an external checking unit by a control unit of the exhaust gas system. In the external checking unit, an evaluation of the exhaust gas system as “manipulated” or as “not manipulated” takes place. Model values are formed in the control unit, which are at least partially formed from the measured values which are sent to the external checking unit. The external checking unit takes the model values and the measured values into consideration in the evaluation of the exhaust gas system.

A heavy duty truck includes a diesel engine that generates an exhaust gas flow and an exhaust after-treatment system for treatment of the exhaust gas flow. The exhaust after-treatment system includes at least one temperature sensor at an underbody SCR system within the exhaust after-treatment system and a DEF injector upstream of a close-coupled SCR system within the exhaust after-treatment system. The DEF injector is operated to inject DEF into the exhaust gas flow at a rate that varies as a function of a temperature measured by the temperature sensor.

A system includes an exhaust aftertreatment system in exhaust gas receiving communication with an engine including a plurality of cylinders where the engine is structured to operate according to low load conditions and where a controller is structured to determine that at least one diesel emissions fluid (DEF) doser is frozen based on at least one of an ambient air temperature and a DEF source temperature. The controller is structured to operate the engine according to a skip-fire mode in response to a DEF flag indicating that the at least one DEF doser is frozen. The skip-fire mode comprises firing a portion of the plurality of cylinders that is less than a total amount of cylinders of the plurality of cylinders. The controller is structured to discontinue the skip-fire mode in response to determining that the at least one DEF doser is likely thawed.

A method for preheating a catalytic converter which is arranged in the exhaust-gas flow of a motor vehicle and which has an electrically heated catalyst is described. The catalytic converter is preheated with the electrically heated catalyst to a maximum temperature within a period of time before the initial engine starting operation. In the process, the temperature of the electrically heated catalyst and the battery state of the vehicle are monitored. During the preheating, it is checked whether or not the battery state has fallen below a state threshold. If so, the heating of the electrically heated catalyst is stopped, and engine-internal measures are implemented. If not, further heating of the electrically heated catalyst is implemented until the maximum temperature is reached again.

An exhaust treatment device for a diesel engine is provided, which includes a parked regeneration requirement notification component and a parked regeneration start operation component. A regeneration process of the diesel particulate filter (DPF) includes an automatic regeneration process and a parked regeneration process. The automatic regeneration process is automatically started when an estimation value of particulate material (PM) accumulated in the DPF reaches a predetermined automatic regeneration start determination value. The parked regeneration process is performed when first and a second conditions are satisfied. The first condition is that a parked regeneration requirement notification component performs a notification of a parked regeneration requirement when a number of cancellations of the automatic regeneration process reaches a predetermined value. The second condition is that the parked regeneration start operation component is subjected to a start operation during a parked state in which an engine equipped machine is neither traveling nor working.

A process is provided for regenerating an exhaust gas after-treatment device in an exhaust line of an internal combustion engine arrangement, the exhaust line including a particle filter. The process includes identifying when soot loading of the particle filter exceeds a predetermined level. After that, temperature of exhaust gases at the particle filter is maintained within a first temperature range until at least one of a predetermined period of time has lapsed or a determination is made that soot loading of the particle filter is below the predetermined level. After that, the temperature of the exhaust gases at the particle filter is increased to within a second temperature range above the first temperature range. An internal combustion engine arrangement is also disclosed.

An intelligent electronic device (IED) may monitor wet stack residue buildup of a diesel engine. Once the wet stack residue accumulates to a certain amount, the IED may perform a mitigation procedure. Additionally, tracking wet stack residue buildup may allow an IED to attempt to prevent or reduce accumulation of the wet stack residue. The IED may track an operating power level of the diesel engine to estimate the rate of residue buildup.

A method to control an internal combustion engine having an exhaust duct and an exhaust gas after-treatment system comprising at least one catalytic converter arranged along the exhaust duct; an oxygen sensor housed along the exhaust duct and arranged upstream of said at least one catalytic converter; and a burner suited to introduce the exhaust gases into the exhaust duct upstream of the oxygen sensor the method provides the steps of identifying the operation phases in which the internal combustion engine is turned off and the burner is turned on so that the oxygen sensor is exclusively hit by the exhaust gases produced by the burner; acquiring the signal generated by the oxygen sensor; and using the signal generated by the oxygen sensor to determine the objective fuel flow rate and the objective air flow rate to be fed to the burner.

A method detects a manipulation of an exhaust gas system, in which measured values are sent to an external checking unit by a control unit of the exhaust gas system. In the external checking unit, an evaluation of the exhaust gas system as “manipulated” or as “not manipulated” takes place. Model values are formed in the control unit, which are at least partially formed from the measured values which are sent to the external checking unit. The external checking unit takes the model values and the measured values into consideration in the evaluation of the exhaust gas system.