A method for evaluating a service interval for replacing a filter of a system for extracting an aqueous liquid from a motor vehicle tank in response to the risk of progressive clogging of said filter from use. A compound clogging risk decision value (K) is generated (320) on the basis of the sum of a plurality of elementary values (k1, k2, k3, k4) of the clogging risk, each related to a risk criterion depending on the operation of the extraction system since commissioning of the filter. The compound clogging risk decision value is compared (340) to a threshold value, and an alert to replace the filtration device is generated (351, 352) if the compound clogging risk value exceeds the threshold value.

A reduction device includes a housing defining an input chamber configured to receive exhaust from a power source, an output chamber, an exhaust channel configured to direct the exhaust from the input chamber to the output chamber, and a longitudinal axis. The reduction device also includes a treatment unit disposed in the exhaust channel and along the longitudinal axis. The treatment unit is configured to at least partly remove pollutant species from the exhaust. The reduction device also includes an attenuation component disposed in the housing and radially outward of the treatment unit. The attenuation component is fluidly connected to the exhaust channel, and is configured to attenuate a range of frequencies corresponding to operation of the power source. Additionally, the exhaust channel prohibits exhaust entering the input chamber from exiting the housing without passing through the treatment unit.

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 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 and system for detecting whether a pressure line in a diesel exhaust fluid (DEF) delivery system has an obstruction. The system includes an electronic control unit with an electronic processor that is configured to receive an unfiltered pressure signal from a pressure sensor; to electronically filter the unfiltered pressure signal to determine a dosing pressure signal; to determine an integrated value based on the dosing pressure signal; and to determine whether the pressure line is obstructed by comparing the integrated value with a predetermined threshold.

An exhaust aftertreatment system including a selective catalytic reduction device (SCR), a NOx sensor and a reductant injection system is described. A method for controlling the reductant injection system to inject reductant into the exhaust gas feedstream upstream relative to the SCR includes monitoring engine operation, and determining an initial reductant dosing rate responsive to the engine operation. A dosing perturbation is induced in the reductant dosing rate. The exhaust gas feedstream is monitored via the NOx sensor, and a reductant dosing correction term is determined based upon the monitoring. A final dosing rate for controlling the reductant injection system is determined based upon the initial reductant dosing rate, the dosing perturbation, and the reductant dosing correction term

An apparatus includes a dosing module structured to suspend dosing in an exhaust aftertreatment system; a selective catalytic reduction (SCR) inlet NOx module structured to interpret SCR inlet NOx data and an SCR inlet temperature; a SCR outlet NOx module structured to interpret SCR outlet NOx data; and a system diagnostic module structured to determine an efficiency of a SCR system based on the SCR inlet and outlet NOx data over a range of SCR temperatures, wherein the system diagnostic module is further structured to determine a state of at least one of a diesel oxidation catalyst (DOC), a diesel particulate filter (DPF), and the SCR system based on the SCR efficiency at an elevated SCR temperature range and the SCR efficiency at a relatively lower SCR temperature range relative to a high SCR efficiency threshold and a low SCR efficiency threshold.

An arrangement for testing or treating a dosing valve of a dosing device of a dosing system in a vehicle includes connecting an electrical test drive to an electrical connector of the dosing device and connecting a dosing tester to a liquid inlet of the dosing device. Thereafter, an outlet valve of the dosing tester is opened to provide liquid under pressure to a liquid inlet of the dosing device. After a first given time, the electrical test drive provides pulses to repeatedly attempt to open the dosing valve. Upon a reduction in liquid level of liquid within the dosing tester in response to opening of the dosing valve, an operator closes the outlet valve of the dosing tester to discontinue the treatment.

Operating an engine exhaust aftertreatment system includes receiving fluid pressure data of a reductant pump, determining a pump operating state, and comparing a pump health parameter to a prognostic pump failure criterion based upon the determining a pump operating state. Operating an engine exhaust aftertreatment system further includes outputting a pump health alert based upon a difference between the pump health parameter and the prognostic pump failure criterion. Related control logic is also disclosed.

Systems and methods are disclosed for determining or diagnosing a reagent dosing system failure to provide sufficient reagent to an exhaust aftertreatment system that includes an SCR catalyst to satisfy a reagent dosing command.