Abstract: An engine exhaust aftertreatment system is disclosed. The system may comprise: an internal combustion engine having an intake passage and an exhaust passage; a turbocharger fluidly connected to the internal combustion engine, the turbocharger including a compressor and a turbine, the compressor being in fluid communication with the intake passage, and the turbine being in fluid communication with the exhaust passage; a reductant injector situated downstream of the turbocharger, wherein the reductant injector is closely coupled to the turbocharger such that a reductant is injected into an exhaust flow of the turbocharger; a first container downstream of the reductant injector, the first container including a multi-functional catalyst (MFC); and a second container downstream of the first container, the second container including a selective catalytic reduction (SCR) component and an Ammonia catalyst (AMOx) component.

Abstract: A heavy-duty truck has a diesel engine, an exhaust after-treatment system, and an engine control unit. The exhaust after-treatment system includes a close-coupled selective catalytic reduction system and an underbody selective catalytic reduction system, a first NOx sensor upstream of the close-coupled selective catalytic reduction system, a second NOx sensor between the two selective catalytic reduction systems, and a third NOx sensor downstream of the underbody selective catalytic reduction system. The engine control unit may perform methods allowing intrusive diagnostics to be performed on exhaust gas NOx sensors using the selective catalytic reduction systems during normal operation of the heavy-duty truck.

Abstract: An engine exhaust aftertreatment system is disclosed. The system may comprise: an internal combustion engine having an intake passage and an exhaust passage; a turbocharger fluidly connected to the internal combustion engine, the turbocharger including a compressor and a turbine, the compressor being in fluid communication with the intake passage, and the turbine being in fluid communication with the exhaust passage; a reductant injector situated downstream of the turbocharger, wherein the reductant injector is closely coupled to the turbocharger such that a reductant is injected into an exhaust flow of the turbocharger; a first container downstream of the reductant injector, the first container including a multi-functional catalyst (MFC); and a second container downstream of the first container, the second container including a selective catalytic reduction (SCR) component and an Ammonia catalyst (AMOx) component.

Abstract: An aftertreatment device includes flow guides disposed within a dosing conduit. Exhaust enters through a perforated region of the dosing conduit and passes through the flow guides. The flow guides induce swirling or other turbulence to mix injected reactant with the exhaust gas. Various types of flow guides include cantilevered vanes, guide passageways, and louvered openings of a second conduit. Some types of flow guides induce localized mixing to inhibit deposit formation at the doser mounting unit. Other types of flow guides induce mixing downstream of the dosing conduit.

Abstract: The present disclosure relates to an exhaust pipe apparatus. The exhaust pipe apparatus includes a first exhaust pipe provided to directly discharge exhaust gas discharged from a combustion engine to the outside, a second exhaust pipe connected in parallel with the first exhaust pipe and having a branch pipe connected to one side thereof such that the exhaust gas is directly discharged to the outside or discharged through the branch pipe, and a first damper installed in the second exhaust pipe to control a flow of the exhaust gas to be directly discharged to the outside or discharged through the branch pipe.

Abstract: A monitoring and control system for a flow duct and a method for determining a component status of an operational component disposed within a flow passage of the flow duct utilizing the system are provided. In one exemplary aspect, the system includes at least two sensors that are disposed within the flow passage and configured to sense a characteristic of a fluid flowing therethrough. The sensors may be averaging sensors. Each sensor extends circumferentially about an axial centerline defined by the flow duct. The sensors are arranged in an overlapped arrangement. Particularly, the sensors extend circumferentially about the axial centerline such that the sensors physically overlap one another circumferentially. Additionally, the sensors may be disposed within the same or substantially the same plane axially. Signals generated by the sensors may be utilized to monitor and control the fluid and various operational components disposed within the flow passage.

Abstract: Proposed is a gas heat-pump system capable of supplying recirculation exhaust gas using a motor-driven turbocharger and thus actively controlling an amount of flowing recirculation exhaust gas and pressure thereof.

Abstract: A vehicular thermal management system is provided that includes an internal combustion engine, a heat recoverer, an engine oil heat exchanger, a drivetrain oil heat exchanger, a coolant pump, and a coolant circuit that fluidly connects the preceding components. The drivetrain oil heat exchanger and the engine oil heat exchanger are arranged in series within the coolant circuit.

Abstract: An example system includes an engine and an exhaust passage fluidly coupled to the engine. A waste heat recovery system includes a boiler operatively coupled to the exhaust passage, and a condenser fluidly coupled to the boiler. An integrated cooling system includes an engine cooling circuit, a waste heat recovery cooling circuit, a waste heat recovery bypass valve, and a controller. The waste heat recovery bypass valve is operatively coupled to the exhaust passage upstream of the boiler, and is selectively controllable so as to direct at least a portion of the exhaust gas through an exhaust bypass passage so as to bypass the boiler. The controller is in operative communication with the waste heat recovery bypass valve. The controller is structured to determine a cooling demand of the engine, and to control a valve position of the waste heat recovery bypass valve based on the cooling demand.

Abstract: A muffler assembly includes first, second, and third mufflers. The first muffler includes a first housing and an X-pipe that is at least partially disposed within the first housing. The X-pipe has first and second inlets and first and second outlets that are all fluidly connected to one another. The first and second inlets receive exhaust gas from the engine. The second muffler includes a second housing and a first Y-pipe that is at least partially disposed therein. The first Y-pipe has a third inlet that receives exhaust gas from the first outlet, and third and fourth outlets. The third muffler includes a third housing and a second Y-pipe that is at least partially disposed therein. The second Y-pipe has a fourth inlet that receives exhaust gas from the second outlet, and fifth and sixth outlets. The first, second, and third housings are spaced apart from one another.

Abstract: Methods and systems are provided for waking up a powertrain control module of an engine-driven vehicle during engine soak to perform an offset test of an exhaust NOx sensor. In one example, a method includes determining a duration to delay waking up the powertrain control module based on exhaust temperature at vehicle-off, waking up the powertrain control module after the duration has expired, and then initiating heating of the NOx sensor. After the NOx sensor lights off, heating continues for an additional duration before offset testing of the NOx sensor is performed.

Abstract: A method for operating a drive device includes heating a hot air stream with a heating device integrated in a cylinder head of an internal combustion engine of the drive device, wherein the internal combustion engine is connected with an exhaust gas system; mixing the hot air stream upstream of a catalytic converter with a cold fresh air stream for adjusting a defined temperature of the hot air stream; and supplying the hot air stream having the adjusted defined temperature to the catalytic converter in at least one operating state of the internal combustion engine so as to heat the catalytic converter.

Abstract: A control apparatus: controls air fuel ratios so that while combustion is performed sequentially through a plurality of cylinders, at least one cylinder where rich combustion is performed and the other cylinders where lean combustion is performed are generated; makes an internal combustion engine execute a catalyst warming operation for promoting warm-up of a three-way catalyst; and controls a second motor generator so that a torque difference between output torque from a rich cylinder where the rich combustion is performed and output torque from a lean cylinder where the lean combustion is performed is eliminated on an output shaft during the catalyst warming operation.

Abstract: Methods and systems are provided for controlling exhaust flow and recovering heat from exhaust gas under different operating conditions. In one example, motive flow of fresh air via an ejector coupled to an exhaust bypass assembly may be utilized to divert exhaust through a heat exchanger during cold-start conditions and heat extracted from the exhaust gas may be utilized for passenger cabin heating and other vehicle heating demands. The exhaust bypass assembly may also be used for EGR delivery wherein the exhaust heat exchanger may be used as an EGR cooler.

Abstract: An exhaust treatment system comprising: a first dosage device, arranged to supply a first additive into said exhaust stream; a first reduction catalyst device, downstream of said first dosage device arranged for reduction of nitrogen oxides in said exhaust stream through the use of said first additive; a particulate filter, at least partly comprising a catalytically oxidizing coating, which is downstream of said first reduction catalyst device to catch soot particles, and to oxidize one or several of nitrogen oxide and incompletely oxidized carbon compounds in said exhaust stream; a second dosage device, downstream of said particulate filter to supply a second additive into said exhaust stream; and a second reduction catalyst device, downstream of said second dosage device for a reduction of nitrogen oxides in said exhaust stream, with the use of at least one of said first and said second additive.

Abstract: A control apparatus for an internal combustion engine having a limiting current sensor includes an electronic control unit. The electronic control unit is configured to: (i) calculate a parameter relating to SOx contained in a detection subject gas using an output current of the sensor obtained when voltage reduction control is implemented to reduce an applied voltage applied to the sensor from a parameter calculation voltage; and (ii) implement the voltage reduction control when an oxygen concentration of the detection subject gas is less than a predetermined concentration or a low oxygen concentration condition, according to which an oxygen concentration of the detection subject gas is predicted to be less than a predetermined concentration, is established.

Abstract: A method of forcibly regenerating a gasoline particulate filter (GPF) includes a first operation of starting an engine, a second operation of determining whether a coolant temperature in the on-state of the engine is equal to or lower than a predetermined temperature, a third operation of determining whether an idle state of the engine is maintained for a predetermined time or longer when the coolant temperature is equal to or lower than the predetermined temperature, and a fourth operation of switching a fuel injection to an air-fuel (A/F) lean injection and forcibly regenerating the GPF by performing the A/F lean injection when the idle state of the engine is maintained for the predetermined time or longer.

Abstract: An exhaust system is provided for an internal combustion engine having at least a first and a second cylinder, wherein the first cylinder is assigned a first exhaust gas pipe and the second cylinder is assigned a second exhaust gas pipe. The first exhaust gas pipe is assigned a first muffler, and the second exhaust gas pipe is assigned a second muffler. A first damping pipe branches off from the first exhaust gas pipe upstream of a first shut-off element. The damping pipe firstly opens into a first reflection chamber and is subsequently led through the first muffler and opens into the second exhaust gas manifold downstream of a second shut-off element. A second damping pipe branches off from the second exhaust gas pipe upstream of a second shut-off element. The second damping pipe firstly opens into a second reflection chamber and is subsequently led through the second muffler and opens into the first exhaust gas pipe downstream of the first shut-off element.

Abstract: Methods and systems are provided for a 2-port integrated exhaust manifold for an inline-3, inline-6, V-6, and/or V-12 engine. In one example, a system may include an exhaust manifold integrated within a cylinder head of an engine block. The integrated exhaust manifold may include a first set of two runners from a first outer cylinder coupled to a first manifold exhaust port, a second set of two runners of a second outer cylinder coupled to a second manifold exhaust port, and one runner of an inner cylinder coupled to the first manifold exhaust port and another runner of the inner cylinder coupled to the second manifold exhaust port.

Abstract: A vehicle system includes an upstream oxygen monitoring module that monitors an upstream exhaust oxygen sensor and determines an upstream transition period based on a time at which the upstream exhaust oxygen sensor detects a rich-to-lean fueling transition. A delay determining module determines a delay period associated with the upstream exhaust oxygen sensor's detection of the fueling transition. An upstream correcting module determines a corrected upstream transition period based on the upstream transition period and the delay period. A downstream oxygen monitoring module monitors a downstream exhaust oxygen sensor and determines a downstream transition period based on the response of the downstream exhaust oxygen sensor to the fueling transition. An oxygen storage capacity (OSC) determining module determines an OSC period based on the corrected upstream transition period and the downstream transition period.

Abstract: An aftertreatment system comprises a SCR system including at least one catalyst for decomposing constituents of an exhaust gas produced by an engine. An exhaust conduit is fluidly coupled to the SCR system and is structured to deliver the exhaust gas to the SCR system and defines an exhaust conduit opening on a sidewall thereof. A mounting plate is positioned within the opening and includes a plurality of fluid channels. At least one mounting plate opening is defined through the mounting plate downstream of an inlet of the plurality of fluid channels and in fluid communication therewith. The fluid channels are structured to receive and direct at least a pair of exhaust gas streams to a respective opening so that they arrive at the respective opening from different directions. The pair of exhaust gas streams combine with a reductant inserted into the opening before flowing into the exhaust conduit.

Abstract: An exhaust system (1) of an internal combustion engine includes an oxidation catalytic converter (2), a particle filter (3), an injector (4) for injecting a reducing agent, a static mixer-evaporator (5), an SCR catalytic converter (6) and a housing (8). The oxidation catalytic converter is upstream of the particle filter and upstream of the SCR catalytic converter. The injector is upstream of the mixer-evaporator and the mixer-evaporator is upstream of the SCR catalytic converter. The housing has a centrally inner channel (9), a ring channel (10) concentrically around the inner channel, an eccentrically outer channel (11), a first deflecting chamber (12) connecting the outer channel with the ring channel and a second deflecting chamber (13) connecting the inner channel with the ring channel. The mixer-evaporator is in the inner channel and the oxidation catalytic converter or particle filter or SCR catalytic converter is ring-shaped and in the ring channel.

Abstract: An exhaust-gas treatment unit includes a housing with a first end and an oppositely disposed second end, a tube extending from the first end to the second end and serving as an inflow region for an exhaust gas, a deflecting region in the vicinity of the second end for the exhaust gas, and a return flow region extending between the tube and the housing. In the deflecting region, the exhaust gas is mixed and transferred into the return flow region. A method for mixing an exhaust gas in an exhaust-gas treatment unit and a vehicle having the exhaust-gas treatment unit and carrying out the method, are also provided.

Abstract: A cleaning system and method of cleaning filters that removes the ash in the plugged regions is disclosed. The filter is subjected to vibrations, which serve to loosen trapped and packed retentate from the filter. The loosened retentate is then captured by a collection bin. The cleaning system can be integral with the intended application, such as within an automobile. In another embodiment, the cleaning system is a separate cleaning station, where the filter is removing from its intended application, cleaned, and then reinstalled.

Abstract: A method for operating an exhaust emission control system of a motor vehicle internal combustion engine, in the exhaust gas line of which an oxidation-catalytically active exhaust emission control component is arranged upstream of a SCR-catalyst is provided. An ageing state of the oxidation-catalytically active exhaust emission control component is determined by correlating a hydrocarbon fraction present in the exhaust emission upstream of the oxidation-catalytically active exhaust emission component with a simultaneous nitrogen oxide conversion of the SCR-catalyst.

Abstract: A device for recovering the waste heat energy having a Clausius-Rankine circuit with a line system conveying a working medium via which at least one vaporizer for vaporizing the working medium, an expansion device for expanding the vaporized working medium to produce mechanical work, a condenser for fluidizing the vaporized and expanded working medium as well as a delivery pump for condensing and conveying the working medium through the line system are fluidically connected to one another. A compensation tank supplies additional working medium volume and is connected to a fluid line and can be fluidically separated from the line system via a valve that is controllable via a control device connected to a sensor for detecting working medium temperature and/or pressure, such that a working medium volume is transferred from the compensation tank into the line system or from the line system into the compensation tank.

Abstract: Methods and systems are provided for adjusting a volume control valve attached to a branch of a split exhaust manifold in a boosted engine system. Volume control valve adjustments are used at different engine operating conditions to improve engine performance and boost response. One example method includes closing the volume in response to a tip-in when increased boost is needed for exhaust turbine spool-up.

Abstract: The invention relates to a system for recovering energy from an exhaust gas circuit (3) of a heat engine (1), including an exhaust gas by-pass pipe (12) that includes a heat exchanger with two compartments, and has a first manifold (14) leading into one compartment (16) and a second manifold (15) leading into the other compartment (17), said system comprising a first valve (18) installed in the exhaust circuit (3) and capable of controlling the flow of gases into each of said manifolds (14, 15), and a second valve (20) intended to control the flow of gases at the outlet of the heat exchanger (13). The main technical feature of a system for recovering energy according to the invention is that the first valve (18) can only be used in two positions, a first position wherein same seals the first manifold (14), and a second position wherein same seals the exhaust circuit (3) and only allows the exhaunt gases to flow into the first manifold (14).

Abstract: A method for operating a turbocharged engine is disclosed. In one example, during a first condition an engine operation is adjusted in response to a turbocharger expansion ratio exceeding a first limit and during a second condition an engine operation is adjusted in response to the turbocharger expansion ratio exceeding a second limit that differs from the first limit. Degradation of the engine may be reduced under some engine operating conditions by adjusting engine operation in response to the turbocharger expansion ratio.

Abstract: An exhaust system, comprising a LP-EGR system that couples an exhaust system to an intake system and an exhaust pipe within the exhaust system with a turn greater 90 degrees and less than 270 degrees between front and rear tires and upstream of a LP-EGR exhaust inlet; and a muffler positioned in the exhaust system downstream of the LP-EGR exhaust inlet and forward of the front tires. By shortening the LP-EGR path, back pressure to sustain EGR flow can be maintained without the use of a back pressure valve.

Abstract: A turbocharger controller includes a turbocharger compressor temperature module having a compressor inlet air temperature input, and a turbocharger compressor pressure module including a compressor inlet pressure input and a compressor outlet pressure input. A memory module includes a compressor outlet temperature calibration map and a compressor pressure ratio look-up table. A turbocharger boost pressure ratio control module is operatively connected to the turbocharger compressor temperature module, the turbocharger compressor pressure module, and the memory module. The turbocharger boost pressure ratio control module is configured to selectively compare compressor outlet pressure and compressor inlet pressure with values in the compressor ratio look-up table to determine a turbocharger boost pressure set point establishing a desired compressor outlet temperature.

Abstract: An exhaust system with post-operation cooling for a vehicle is provided. The vehicle generally has a heat generating device that generates exhaust gas. The exhaust system includes an exhaust gas conduit through which at least a portion of the exhaust gas is flowable and dischargeable, and at least one exhaust gas component in fluid communication with the exhaust gas conduit. The exhaust system also includes an air intake conduit through which outside air is flowable, and an air pump in fluid communication with the air intake conduit. The air intake conduit is in fluid communication with the exhaust gas conduit upstream of the at least one exhaust gas component. The air pump is configured to draw the outside air into the air intake conduit such that the outside air is supplied to the exhaust gas conduit to cool the at least one exhaust gas component.

Abstract: The present disclosure relates to an energy recovery system for a vehicle powered by an engine. The energy recovery system includes a thermoelectric module which is interfaced with a heat source of the vehicle. The heat source generates waste heat. Further, the waste heat provides a high temperature heat source for the thermoelectric module. A low temperature heat source is also interfaced with the thermoelectric module. A temperature difference between the high temperature heat source and the low temperature heat source generates thermoelectric power. A controller is configured to control a parameter of the engine to maintain an optimal value of the temperature difference between the high temperature heat source and the low temperature heat source.

Abstract: Provided is a control apparatus for a supercharged internal combustion engine. A turbo supercharger, an exhaust bypass passage, a WGV capable of switching the opening and closing of the exhaust bypass passage, and variable valve operating mechanisms capable of changing a valve overlap period are included. The valve overlap period is shortened so that the fresh air blow-through amount Gsca becomes equal to or smaller than a predetermined blow-through determination value Gjudge when the blow-through amount Gsca is larger than the blow-through determination value Gjudge. The WGV is opened when the blow-through amount Gsca is still larger than the blow-through determination value Gjudge after the valve overlap period has been shortened.

Abstract: System for protecting a turbo-supercharging unit (T, C), in particular for preventing a respective damage when a pressure of a respective lubrication oil is insufficient, comprising first bypass means (OV, GB) of exhaust gas, controlled as a function of a pressure of the lubricating oil of the turbo-supercharging unit (T, C), in order to allow to at least a part of the exhaust gas to bypass the turbine (T) when the pressure is below a first predetermined threshold.

Abstract: Systems and methods for operating an engine that includes an exhaust gas heat recovery system are described. The system may reduce engine warm-up time and increase an amount of time an engine of a hybrid vehicle is deactivated while the hybrid vehicle is powered by a motor. In one example, a phase change material selectively stores and releases exhaust gas energy from and engine to improve vehicle operation.

Abstract: A mixing chamber for an exhaust system is disclosed. The mixing chamber includes a tapering cross sectional area perpendicular to a longitudinal axis of the mixing chamber. The mixing chamber includes a first end having a first cross sectional area and a second end having a second cross sectional area. The second cross sectional area is less than the first cross sectional area. The second end is configured to receive an injector. The mixing chamber includes a first exhaust conduit fluidly connected to the first end of the mixing chamber and defining a first exhaust gas flow path into the mixing chamber substantially perpendicular to the longitudinal axis. The mixing chamber also includes a second exhaust conduit fluidly connected to the first end of the mixing chamber and defining a second exhaust gas flow path out of the mixing chamber substantially in the direction of the longitudinal axis.

Abstract: A method for operating an exhaust gas treatment system that includes an SCR catalytic converter is provided. Either a model-based filling level regulation for achieving the target filling level or a model-based efficiency control for achieving the target efficiency is performed according to presettable values for certain operating variables such as a temperature of the exhaust gas or of the SCR catalytic converter.

Abstract: A method for correcting the reduced mass flow rate of a compressor in an internal combustion engine turbocharged by means of a turbocharger provided with a turbine and with a compressor; the internal combustion engine comprising an intake manifold and an exhaust manifold, and being set up to allow the passage of air from the intake manifold to the exhaust manifold; the method comprising determining, in a design stage, a control law that provides an objective opening of a control actuator of the wastegate as a function of an actual supercharging pressure and of a reduced mass flow rate of the compressor; and correcting the reduced mass flow rate of the compressor as a function of the enthalpy of a gas mixture flowing through the turbine of the turbocharger.

Abstract: A method for improving fuel efficiency of a vehicle and an exclusive energy saving and emission reduction device thereof are provided. The key points of the technical solutions are as follows. An exhaust separation device is installed in a crankcase of an engine. An oil-gas separation technology is adopted to manufacture an oil-gas separator and a diffusion vortex chamber. According to an aerodynamic principle, the separation degree of the exhaust is improved through compression and high speed vortex in the energy saving device, in such a manner that engine oil vapor in the exhaust is separated from combustible mixed gases, and then sent to the engine via an air intake throttle. The present invention enables complete combustion of the fuel, so as to achieve effects of oil-saving and emission-reducing.

Abstract: An engine system, comprising an externally filled fuel tank with an external fill port; a separator for separation of fuel based on octane level, the separator having a high octane outlet and a low octane outlet; a secondary fuel tank with an amount of fuel located therein and a return line, the secondary fuel tank fluidically coupled to the low octane outlet of the separator and the return line fluidically coupling the externally filled fuel tank to the high octane outlet of the separator or the secondary fuel tank fluidically coupled to the high octane outlet of the separator and the return line fluidically coupling the externally filled fuel tank to the low octane outlet of the separator.

Abstract: An engine method, comprising delivering high octane fuel to a high octane fuel tank and delivering low octane fuel to a low octane fuel tank and injecting atmospheric air into an exhaust system for secondary air injection in response to delivering low octane fuel to an engine.

Abstract: Methods and systems are provided for managing a compressor temperature using EGR to address surge and condensation. A variable mixture of cooled compressor recirculation flow and hot EGR is provided to a compressor inlet. A composition of the mixture is adjusted to maintain a compressor inlet temperature sufficiently warm so as to reduce ingestion of condensation, and a compressor outlet temperature sufficiently cold to be within component temperature limits with flow above the surge limit.

Abstract: Methods and systems are provided for reducing condensate accumulation at a charge air cooler (CAC) during cold ambient conditions. A wastegate may be held closed while a compressor recirculation valve is held open during an engine cold start so as to use compressor heating and increased compressor recirculation to expedite CAC heating. EGR delivery is delayed until the CAC is sufficiently warm to reduce the propensity for condensation.

Abstract: Methods and systems are provided for improving a margin to surge. A compressor recirculation valve is held at a semi-open position during steady-state boosted engine operation and operation in a soft surge region. The valve is fully opened to reduce hard surge, or fully closed to meet a transient increase in boost demand.

Abstract: Methods and systems are provided for varying a proportion of compressed air recirculated to a compressor inlet from a location downstream of the compressor and upstream of a charge air cooler and a location downstream of the charge air cooler. A temperature-controlled compressor recirculation flow is used to reduce condensation from EGR being ingested into the compressor. The temperature-controlled compressor recirculation flow is also used to address compressor surge.

Abstract: Methods and systems are provided for coordinating adjustments to a compressor recirculation valve with adjustments to a binary flow turbine scroll valve to reduce surge. The scroll valve is closed to increase turbine energy while the compressor recirculation valve is opened to increase compressor flow. Concurrent adjustments to a wastegate may be used to provide boost pressure control.

Abstract: Methods and systems are provided for varying a proportion of compressed air recirculated to a compressor inlet from a location downstream of the compressor and upstream of a charge air cooler and a location downstream of the charge air cooler. A temperature-controlled compressor recirculation flow is used to reduce condensation from EGR being ingested into the compressor. The temperature-controlled compressor recirculation flow is also used to address compressor surge.

Abstract: Methods and systems are provided for using compressor recirculation flow via a venturi to enhance low pressure EGR flow. The opening of a compressor recirculation valve can be adjusted based on EGR flow demand to recirculate cooled compressed air through a venturi while generating vacuum for drawing EGR. The approach allows for concurrent EGR control and surge control.

Abstract: A method for operating a tank for reducing agent, in particular aqueous urea solution, having a sensor with a first electrical contact and a second electrical contact, includes initially determining a conductance value for liquid reducing agent, a conductance value for frozen reducing agent and a conductance value for air in steps a.1) to a.3. A voltage is then applied between the first electrical contact and the second electrical contact in step b. A conductance value between the first electrical contact and the second electrical contact is then determined in step c. The conductance value determined in step c) is then compared to the conductance values determined in steps a.1) to a.3) and a determination is made as to if liquid reducing agent, frozen reducing agent, or air is present in step d). A motor vehicle in which the method is carried out, is also provided.