A control device for an internal combustion engine including an upstream cleaning device and a downstream cleaning device that are provided in an exhaust gas passage and a temperature sensor that detects a temperature of exhaust gas between the upstream cleaning device and the downstream cleaning device is provided. The control device includes a first temperature estimating unit configured to estimate a temperature of the downstream cleaning device from the temperature of exhaust gas detected by the temperature sensor and a second temperature estimating unit configured to estimate a temperature of the downstream cleaning device without using the temperature of exhaust gas detected by the temperature sensor. An abnormality determining process for the upstream cleaning device is performed when at least the temperature of the downstream cleaning device estimated by the second temperature estimating unit is equal to or greater than a predetermined threshold value.

A cleaning system for removal of contaminants from a surface of a vehicle component exposed to a gas or fluid flow, the cleaning system comprising: an excitation device adapted to be attached to the vehicle component in the vicinity of the surface exposed to contaminants, wherein the excitation device is configured to cause the surface to mechanically vibrate by transferring a vibrational excitation to the surface; wherein the frequency of the vibrational excitation is controllable to be based on the configuration of the vehicle component as well as other modelled/measured parameters.

Various embodiments include a control system for the regeneration of a particle filter in an exhaust gas flow of an internal combustion engine of a hybrid vehicle including an electric machine comprising: a particle filter; a temperature sensor measuring an actual temperature of the filter; a first heat source upstream of the filter; and a controller. The controller is programmed to: determine a temperature difference between a setpoint temperature for regeneration of the particle filter and the actual temperature of the particle filter; calculate a power output difference to be applied based at least in part on the temperature difference; and control the first heat source using the power output difference.

An exhaust apparatus includes a chamber disposed below an engine, an inlet pipe guiding exhaust gas from an exhaust pipe to the chamber, a tail pipe discharging the exhaust gas from the chamber to an outside, a first partition wall partitioning an inside of the chamber to a pair of left and right spaces, and a second partition wall partitioning one of the left and right spaces to a pair of front and rear spaces. Another of the left and right spaces is a first expansion chamber into which the inlet pipe enters. A rear space of the front and rear spaces is a second expansion chamber disposed downstream of the first expansion chamber. A front space of the front and rear spaces is a third expansion chamber disposed downstream of the second expansion chamber, and the tail pipe enters into the front space.

An exhaust system for an internal combustion engine, in the exhaust duct of which a sensor is arranged for determining the exhaust gas composition. Furthermore, upstream of the sensor a guide vane is arranged, which is designed to increase the flow velocity of the exhaust gas in a local flow cross-section of the exhaust duct at the height of the sensor. This makes it possible to provide sufficiently high flow velocities of the exhaust gas at the sensor.

A controller for an internal combustion engine is configured to execute a rich air-fuel ratio control for performing fuel injection while setting a target equivalence ratio such that, at recovery from a fuel cutoff process, an air-fuel ratio of air-fuel mixture is richer than a stoichiometric air-fuel ratio. The controller is configured to execute a target equivalence ratio setting process for setting the target equivalence ratio that is maintained during execution of the rich air-fuel ratio control such that the target equivalence ratio increases as an air excess ratio that is calculated from an output value of a second air-fuel ratio sensor at start of the rich air-fuel ratio control increases.

An exhaust passage including a protrusion which is less likely to receive heat from a gas and hence has high heat-resistance reliability is provided. An exhaust passage includes an exhaust pipe, and a protrusion continuously formed over a range of a part of an inner surface of the exhaust pipe in a circumferential direction thereof, the protrusion being inclined toward a direction in which the exhaust pipe extends, and being configured in such a manner that a cross-sectional area of the exhaust pipe becomes smaller toward a downstream side thereof, in which the exhaust passage further includes a convex part on an inner surface of the protrusion.

A method includes: interpreting first oxygen data acquired by a first nitrous oxide (NOx) sensor indicative of a first amount of oxygen in an exhaust flow at a location in or proximate to an exhaust aftertreatment system, wherein the exhaust aftertreatment system is in exhaust gas receiving communication with an engine; estimating an amount of oxygen in the exhaust flow entering the exhaust aftertreatment system from the engine based on engine operation data; and, determining that the NOx sensor is faulty based on determining that a difference between the first amount of oxygen and the estimated amount of oxygen is greater than a threshold value.

An exhaust sensor includes a sensing element with a ceramic sensing element substrate and a sensing element terminal which is electrically conductive and which is supported by the ceramic sensing element substrate such that the sensing element is configured to sense constituents of exhaust gases when exposed thereto. The exhaust sensor also includes a mating terminal which is electrically conductive and which is in electrical communication with the sensing element terminal. The mating terminal has a base material and a clad material bonded to the base material such that the clad material contacts the sensing element terminal and such that the clad material is located between the sensing element terminal and the base material, thereby providing the electrical communication. The clad material is an alloy which is less than or equal to 20% iron, greater than or equal to 40% nickel, and greater than or equal to 13% chromium.

An abnormality determination apparatus for an ammonia sensor is usable in an exhaust purification system including a catalyst, a supply apparatus, an ammonia sensor, an NO.sub.X sensor, and an oxygen sensor. During a continuation period within which ammonia supply to the catalyst continues after the supply apparatus stops supply of reductant, the abnormality determination apparatus calculates the ammonia concentration on a downstream side of the catalyst as a first concentration value, based on an output of the ammonia sensor and an output of the oxygen sensor. During the continuation period, the abnormality determination apparatus calculates the ammonia concentration on the downstream side of the catalyst as a second concentration value, based on an output of the NO.sub.X sensor and the output of the oxygen sensor. The abnormality determination apparatus determines presence or absence of abnormality in the ammonia sensor based on the first concentration value and the second concentration value.