391 results about "Exhaust gas sensor" patented technology

A system for a vehicle comprising of an engine including a first cylinder group and a second cylinder group; a linear exhaust gas sensor coupled exclusively to the first cylinder group; a switching exhaust gas sensor coupled exclusively to the second cylinder group; and a controller configured to operate the engine in at least a first mode and a second mode, where in the first mode the first and second cylinder groups combust air and fuel, where in the second mode at least one of the first and second cylinder groups combusts air and injected fuel and the other one of the first and second cylinder groups pumps air without injecting fuel, and where the controller is further configured to estimate torque of the engine in each of the first and second modes of operation based on the air-fuel ratio of the first cylinder group and the air-fuel ratio of the second cylinder group independent of the switching sensor and dependent on the linear sensor.

A system and method for controlling an internal combustion engine for low emissions include an inner feedback control loop to control the engine fuel/air ratio with feedback provided by a first exhaust gas sensor and an outer feedback control loop that modifies the fuel/air ratio reference provided to the inner feedback control loop based on feedback signals provided by the first exhaust gas sensor and a second exhaust gas sensor. The fuel/air ratio reference signal controller adapts to the oxygen storage capacity of the catalyst by modeling the catalyst as an integrator with an unknown gain and estimating the catalyst gain based on the first and second exhaust gas sensor signals. Using the estimated catalyst gain, an adaptive controller gain factor is determined and subsequently used to determine the fuel/air ratio reference signal provided to the fuel/air ratio controller of the inner feedback control loop.

Various systems and methods are described for an exhaust gas sensor coupled to an exhaust system of an engine. One example method comprises, during selected engine fueling conditions, alternating between applying different voltages to the sensor; and identifying an amount of alcohol in fuel injected to the engine based on sensor outputs at the different voltages.

An exhaust system for a motorcycle having an engine mounted on a front half of a body frame of the motorcycle includes a plurality of first exhaust pipes extending from exhaust ports of the engine, a collecting section at which the first exhaust pipes are collected, a second exhaust pipe including a substantially straight portion connected to a downstream side of the collecting section and disposed under a crankcase of the engine, an expansion chamber connected to a downstream side of the second exhaust pipe and located under a rear wheel suspension arranged behind the engine, an exhaust outlet disposed on a most downstream portion of the expansion chamber, and an exhaust throttle valve and an exhaust gas sensor disposed on the straight portion of the second exhaust pipe.

As one example, an engine system for a vehicle is provided, comprising an internal combustion engine including an air intake system and an exhaust system; a first turbocharger including a first compressor arranged along a first branch of the air intake system, a first turbine arranged along a first branch of the exhaust system, and a first turbine bypass passage include a first wastegate; a second turbocharger including a second compressor arranged along a second branch of the air intake system, a second turbine arranged along a second branch of the exhaust system, and a second turbine bypass passage including a second wastegate; a first exhaust gas sensor arranged along the first branch of the exhaust system downstream of the first turbine and first wastegate; a second exhaust gas sensor arranged along the second branch of the exhaust system downstream of the second turbine and the second wastegate; and a control system configured to command both the first wastegate and the second wastegate to a closed position or an opened position and to indicate one of said wastegates as unresponsive to said command in response to a temperature difference between the first and second branches indicated by the first and second exhaust gas sensors.

A deterioration detecting apparatus for an exhaust gas sensor of an internal combustion engine, the exhaust gas sensor including a sensor element and a heater that heats the sensor element, computes a first sensor characteristic parameter, which is related to a characteristic of the sensor element, by estimating an interchange state of thermal energy between the sensor element and a periphery of the sensor element. The deterioration detecting apparatus senses impedance of the sensor element. The deterioration detecting apparatus computes a second sensor characteristic parameter, which is related to the characteristic of the sensor element, based on the sensed impedance. The deterioration detecting apparatus determines a degree of deterioration of the exhaust gas sensor by comparing the first sensor characteristic parameter and the second sensor characteristic parameter.

Described herein is a sensor module for sensing characteristics of a fluid flowing through a fluid conduit. The sensor module includes a sample probe with at least one sample arm that extends radially inwardly from a sidewall portion of the fluid conduit to a center portion of the fluid conduit, defines a fluid flow channel, and includes a plurality of inlet apertures. The sample probe also includes a sensor well that is located at a radially outer end of the at least one sample arm. The sensor well defines an interior volume that is in fluid communication with the fluid flow channel, an upstream portion closed to an first portion of the fluid conduit upstream of sensor well, and a discharge aperture open to a second portion of the fluid conduit downstream of the sensor well. The sensor module also includes a sensor positioned in the interior volume.

A system for improving operation of an engine having a particulate matter sensor is presented. The system may be used to improve engine operation during cold starts especially under conditions where water vapor or entrained water droplets are present in vehicle exhaust gases. In one embodiment, an engine controller that activates a heater of an exhaust gas sensor after an output of a particulate matter sensor exceeds a threshold value after an engine is started.

A vehicle includes an engine, a booster, an exhaust gas sensor and a self-calibration arrangement for the exhaust gas sensor. When sensor calibration check is desired, a controlling unit opens a valve in order to subject a sensing element of the sensor to a supply of gas having a known gas concentration. Gas concentration signals from the sensor are compared with known concentration values, with the results being used to re-calibrate the sensor. The supply of gas can be received directly from the booster or from an optional reservoir. The invention is particularly applicable for use with a universal exhaust gas oxygen sensor in a vehicle powered by a diesel engine.

A system and method for controlling an internal combustion engine determine a catalyst gain based on an exhaust gas sensor positioned upstream relative to a catalyst and at least one exhaust gas sensor positioned downstream relative to at least a portion of the catalyst and use the gain to determine the condition or performance of the catalyst. The gain may be determined by modeling the catalyst as an integrator with an unknown gain and estimating the gain using a polynomial approximation. The gain is compared to an expected value or threshold associated with current operating conditions, such as catalyst temperature and/or mass air flow.

Methods and systems are provided for estimating a PCV flow to an engine based on the output of an exhaust gas oxygen sensor. During DFSO conditions, a reference voltage of the sensor is modulated initially with an intake throttle open and then with the intake throttle closed. PCV flow leaking past the piston valves in an aging engine, as well as an ambient humidity estimate, are inferred based on the outputs of the sensor during the modulating with the intake throttle open and closed.

Various methods and system are described for determining ambient humidity via an exhaust gas sensor disposed in an exhaust system of a variable displacement engine. A reference voltage of a sensor coupled to an inactive engine bank is modulated between a first and second voltage to estimate ambient humidity. Concurrently, a reference voltage of a sensor coupled to an active engine bank is modulated between the first and second voltage, or at the first voltage, to estimate fuel alcohol content, or exhaust air-fuel ratio, respectively.

The invention provides a control strategy and a control system to control a gas sensor to a target operating temperature. It relies upon both feedback and model-based feedforward control systems to achieve and then maintain the sensor at the target operating temperature. The mechanization includes a gas sensor with a heating element in a feedstream. The control strategy employs a control system for the heating element that is based upon the target operating temperature, the temperature of the heating element, and an effect of the feedstream and mounting structure on the temperature of the sensor. The control strategy enables the control system to optimize the heating of a sensor during warm-up and steady state operations.

Embodiments for adjusting engine operating parameters based on output from an exhaust humidity sensor are provided. One example method for an engine comprises based on a dew point of exhaust gas, adjusting an exhaust gas sensor heater configured to heat an exhaust gas sensor disposed in an exhaust passage of the engine, the dew point based on output from a humidity sensor disposed in the exhaust passage.

An operating method is provided for a motor vehicle diesel engine having an exhaust emission control system that includes a three-way catalytic converter and an SCR catalytic converter situated one behind the other in the flow direction of the exhaust gas. The diesel engine is operated, at least intermittently, with an air-fuel ratio of approximately λ=1.0 in a first operating range in which the SCR catalytic converter falls below a predefinable minimum temperature and with excess air that is typical for normal diesel engine operation in a second operating range in which the SCR catalytic converter exceeds the predefinable minimum temperature. An output signal of an exhaust gas sensor situated downstream from the three-way catalytic converter and which is correlated with a NOx concentration of the exhaust gas is used to set the air-fuel ratio in the first operating range.

The heater control apparatus comprises an exhaust gas sensor 6 for detecting an oxygen concentration in exhaust gases of an internal combustion engine, a heater 5 for heating this exhaust gas sensor 6 to a predetermined temperature, a power source including a battery 2 for supplying electric power to this heater 5 and a charging generator 4 for charging this battery 2, a switching element 19 inserted into a circuit for supplying electric power to the heater 5 from the power source, control means 12 for performing current-carrying control of the switching element 19 so as to maintain a temperature of the exhaust gas sensor 6 at a predetermined value, and an overvoltage detection element 28 for outputting an abnormal detection signal when a voltage of the power source exceeds a predetermined value, and it is constructed so that the switching element 19 is broken to stop the passage of current to the heater 5 by the abnormal detection signal of the overvoltage detection element 28 when a voltage of the charging generator 4 abnormally increases due to disconnection etc. of the battery 2 of the power source.

A target value Vtgt for an output Vout of an O₂ sensor 8 (an exhaust gas sensor) disposed downstream of a catalytic converter 4 is set variably depending on a temperature T_O2 of an active element 10 of the O₂ sensor 8 by a target value setting unit 18, and the air-fuel ratio of an exhaust gas is controlled by an air-fuel ratio control unit 17 to converge the output Vout to the target value Vtgt. An exhaust gas temperature Tgd is estimated by an exhaust temperature observer 19, and the temperature T_O2 of the active element 10 is sequentially estimated by an element temperature observer 20 using the estimated value of the exhaust gas temperature Tgd. A heater 13 of the O₂ sensor 8 is controlled by a heater controller 22 to keep the temperature T_O2 of the active element 10 at a predetermined target value R. The air-fuel ratio is thus controlled to maintain a desired exhaust gas purifying capability of the catalytic converter irrespective of the temperature of the active element of the exhaust gas sensor.