A method for ascertaining a fill level of at least one exhaust-gas component, which can be stored in a catalytic converter and which is generated in a combustion process, in the catalytic converter, wherein a variation of the fill level of the at least one exhaust-gas component in the catalytic converter during the combustion process is determined, wherein, during time periods in which the combustion process is not operated, a diffusion-induced change of the fill level of the at least one exhaust-gas component in the catalytic converter is determined, and wherein, on the basis of the determined variation during the combustion process and the diffusion-induced change, a fill level of the at least one exhaust-gas component in the catalytic converter is ascertained. The invention furthermore relates to a processing unit and to a computer program for carrying out such a method.

Methods and systems are provided for carrying out diagnostics of a bleed canister of an evaporative emissions control system in a vehicle. In one example, a method may include, loading the bleed canister during a refueling event, and then during an immediately subsequent engine start, detecting if the bleed canister is degraded or not based on output of an exhaust gas oxygen sensor.

The exhaust purification device of an internal combustion engine comprises a catalyst 20 arranged in an exhaust passage and able to store oxygen; and an air-fuel ratio control device configured to control an air-fuel ratio of inflowing exhaust gas flowing into the catalyst. The air-fuel ratio control device is configured to perform a distribution forming control controlling the air-fuel ratio of the inflowing exhaust gas so that in the catalyst, a first region with an oxygen storage amount of equal to or greater than a predetermined value and a second region with an oxygen storage amount of less than the predetermined value are alternately formed along an axial direction of the catalyst. The total number of the first region and the second region formed by the distribution forming control is equal to or greater than three.

A catalytic converter system having oxygen storage materials is disclosed and methods for determining whether to reactivate oxygen storage materials and monitoring failure events of the oxygen storage materials are also disclosed.

A sensor tube structure includes a sensor housing, a sensor mounted on the sensor housing, an external tube mounted at an end of the sensor housing to enclose the sensor, an inner tube provided to be movable inside the external tube, a drive plate in which a sensor hole into which the sensor is inserted is formed, and is coupled to the inner tube, and an actuator mounted on the sensor housing and selectively moving the drive plate.

A gas sensor includes a sensor element, and the sensor element includes a bottomed tubular solid electrolyte, a detection electrode provided on an outer surface of the solid electrolyte, a reference electrode provided on an inner surface of the solid electrolyte. The detection electrode of the sensor element includes a detection electrode section provided at a position on a tip side of an axial direction, an attachment electrode section provided at a position on a base end side of the axial direction, and a lead electrode section provided at a position where the detection electrode section is connected to the attachment electrode section. An insulating layer is provided between a tube of the solid electrolyte and each of the attachment electrode section and the lead electrode section.

A method for diagnosing a plurality of lambda sensors which are arranged upstream of an exhaust gas catalytic converter in a plurality of exhaust gas banks of a multi-flow exhaust gas system of an internal combustion engine. An opposite lambda offset of the lambda sensors is identified (54) when a difference (ΔT) between a measured exhaust gas temperature (T.sub.measure) and a modeled exhaust gas temperature (T.sub.mod) downstream of the exhaust gas catalytic converter overshoots a threshold value (S).

An exhaust aftertreatment system and associated method for purifying an exhaust gas feedstream of a lean-burn or other compression-ignition internal combustion engine is described. An instruction set is executable to determine an engine-out NO2 concentration upstream of an oxidation catalyst and determine a first parameter associated with O2 concentration. A consumption of oxygen in the oxidation catalyst due to oxidation reactions is determined, and a concentration of NO2 generated by the oxidation catalyst is determined based upon the consumption of oxygen in the oxidation catalyst. A concentration of NO2 downstream of the oxidation catalyst is determined. A NO2/NOx ratio in the exhaust gas feedstream downstream of the oxidation catalyst is determined based upon the concentration of NO2 downstream of the oxidation catalyst and the NOx concentration measured by the downstream NOx sensor. The oxidation catalyst is evaluated based upon the NO2/NOx ratio.

A catalytic converter system having oxygen storage materials is disclosed and methods for determining whether to reactivate oxygen storage materials and monitoring failure events of the oxygen storage materials are also disclosed.

The invention presented is a crossover section for a vehicle exhaust system that includes a middle pipe and two outer pipes, each outer pipe in contact with and attached to the middle pipe. Diversion gates extend from the middle pipe into each of the outer pipes to divert a sample of exhaust gas into the middle pipe. A sensor, such as an oxygen sensor, is provided to measure one or more components of the combined exhaust. Also provided is an exhaust system that includes the inventive crossover section and a vehicle that includes one or more of the inventive exhaust systems.