An exhaust gas sensor arrangement structure includes a catalyst which purifies exhaust gas of an engine; and exhaust gas sensors which detect an exhaust gas component of the engine; the catalyst is provided under the engine; and the exhaust gas sensors are provided within a width of the engine in a front/rear direction so that the catalyst is provided between the exhaust gas sensors at front and rear sides of the catalyst.

An aftertreatment system for an internal combustion system includes an exhaust duct, an oxidation catalyst disposed in the exhaust duct and a particulate filter disposed in the exhaust duct downstream of the oxidation catalyst. The internal combustion engine is operated to perform a regeneration process of the particulate filter. A first value of exhaust gas temperature in the exhaust duct between the oxidation catalyst and the particulate filter is determined. A second value of exhaust gas temperature in the exhaust duct downstream of the particulate filter is determined. A malfunctioning of the oxidation catalyst is determined when the first value of exhaust gas temperature is below a first predetermined threshold value thereof and contemporaneously the second value of exhaust gas temperature is above a second predetermined threshold value thereof during the regeneration process.

Determining a functionality of an exhaust gas sensor in an exhaust gas system having a catalytic converter and a first exhaust gas sensor upstream of the catalytic converter and a second exhaust gas sensor downstream of the catalytic converter. The first and the second exhaust gas sensors are heated to a temperature above a minimum operating temperature.; A first sensor signal of the first exhaust gas sensor; and a second sensor signal of the second exhaust gas sensor are determined. The first and the second sensor signals are compared in an operating period in which a temperature of the at least one catalytic converter does not exceed a temperature threshold value; and an operating parameter of the first exhaust gas sensor (121) is determined on the basis the comparison

Methods and systems to control a temperature of a selective catalytic reduction catalyst are disclosed. In one example, a diverter valve that includes two butterfly valves that are coupled together via a shaft is adjusted to control a temperature at an inlet of the selective catalytic reduction catalyst so that the selective catalytic reduction catalyst may operate efficiently.

Systems and apparatuses include a diesel exhaust fluid tank, a first temperature sensor positioned within the diesel exhaust fluid tank and structured to provide first temperature information indicative of a first temperature, and a second temperature sensor positioned within the diesel exhaust fluid tank and structured to provide second temperature information indicative of a second temperature. The systems and apparatuses further include one or more processing circuits including one or more memory devices coupled to one or more processors, the one or more memory devices configured to store instructions thereon that, when executed by the one or more processors, cause the one or more processors to provide energy to a heating system based on the first temperature information and the second temperature information.

To keep medium purification efficiency at a high level and prevent deterioration of emission performance. An aspect of the present invention includes: a downstream equivalence ratio calculation unit that calculates a catalyst downstream exhaust gas equivalence ratio by using a catalyst statistical model that receives at least a detection value of an air-fuel ratio sensor on an upstream side of a catalyst and outputs a catalyst downstream exhaust gas equivalence ratio; an oxygen output calculation unit that calculates an output value of an oxygen sensor by using an oxygen sensor statistical model that receives the catalyst downstream exhaust gas equivalence ratio and outputs an output value of the oxygen sensor on the downstream side of the catalyst; a downstream equivalence ratio correction unit that corrects the catalyst downstream exhaust gas equivalence ratio calculated by the downstream equivalence ratio calculation unit based on a calculation result of the oxygen output calculation unit and the detection value of the oxygen sensor; and an air-fuel ratio control unit that controls an air-fuel ratio of an air-fuel mixture of an internal combustion engine based on the corrected catalyst downstream exhaust gas equivalence ratio and air-fuel ratio target value.

A method is for route identification that is conducive for successful diagnosis of an exhaust gas treatment system of a vehicle. In the method, an ECU in the vehicle receives a value of GPS coordinates from a GPS module, and the ECU retrieves a value of day, date, and time from an ECU clock. The ECU monitors a value of engine operating conditions with reference to the received value of GPS coordinates and the retrieved value of day, date, and time. The ECU identifies a segment of GPS coordinates for successful diagnosis of an exhaust gas treatment system based on the monitored value. Upon the identification, the segment of GPS coordinates is stored in ECU memory.

A computer implemented method to performing sensor analysis in an exhaust gas aftertreatment system (EATS) coupled downstream of an internal combustion engine (ICE). The methodology is specifically adapted for determining a scale factor for a NOx sensor that is arranged downstream of a position where an amount of a reductant is injected into exhaust gases from the ICE.

An assembly for determining lambda values of an exhaust gas of an internal combustion engine is provided. The internal combustion engine is attached to an exhaust gas treatment device with at least one first catalyst and a second catalyst. Additionally, the assembly has the following: a first lambda sensor in a first removal line, wherein the first removal line is designed to remove a part of the exhaust gas upon entering the first catalyst and conduct same back into the exhaust gas treatment device after the exhaust gas passes the first lambda sensor, and the first lambda sensor and at least one part of the first removal line are arranged outside of the exhaust gas treatment device; and a second lambda sensor in a second removal line, wherein the second removal line is designed to remove a part of the exhaust gas between the first catalyst and the second catalyst and conduct same back into the exhaust gas treatment device after the exhaust gas passes the second lambda sensor, and the second lambda sensor and at least one part of the second removal line are arranged outside of the exhaust gas treatment device.

A method is provided for ascertaining a NO.sub.x concentration and an NH.sub.3 slip downstream from an SCR catalytic converter of an internal combustion engine of a vehicle. State variables of an internal combustion engine as first input variables and an updated NH.sub.3 fill level of the SCR catalytic converter as a second input variable cooperate with at least one machine learning algorithm or at least one stochastic model. The at least one machine learning algorithm or at least one stochastic model calculates the NO.sub.x concentration and the NH.sub.3 slip downstream from the SCR catalytic converter as a function of the first input variables and the second input variables and output the same as output variables.