Abstract: The disclosure relates to a method for determination of an operating state of a compressor and/or a rotational speed of a compressor drive of the compressor comprising; measuring, over a time range, a magnetic field associated with one or more phases of an electrical power supply conductor supplying the compressor with electrical power; wherein the magnetic field is measured by a detection element to provide a representation of the magnetic field; determining a frequency spectrum of the representation of the magnetic field over the time range; and analyzing the frequency spectrum of the representation of the magnetic field over the time range to determine an operating state of the compressor and/or to determine a rotational speed of the compressor drive. The disclosure further relates to a device for carrying out the method, a compressor measuring system, and a computer-readable storage medium.

Abstract: A heating system includes at least one electric heater disposed within the fluid flow system. A control device includes a microprocessor and is configured to determine a temperature of the at least one electric heater based on a model and at least one input from the fluid flow system. The control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.

Abstract: The invention relates to a temperature measurement device comprising at least three probes, a computer, the computer being configured to estimate a temperature on the basis of voltage measurements at the output of the probes, characterised in that the probes are connected together in a plurality of meshes mounted in series, with at least one mesh comprising at least two probes mounted in parallel and at least one other mesh comprising a probe or a plurality of probes mounted in parallel.

Abstract: In the abnormality diagnosis device which carries out an abnormality diagnosis of the reducing agent adding device by obtaining a diagnostic parameter which is a parameter correlated with an amount of pressure drop in a reducing agent passage in the case where, from a state in which an addition valve has been closed and in which a voltage to be applied to a pump is controlled to a diagnostic voltage so that the pressure in the reducing agent passage becomes a predetermined pressure, the addition valve is made to open in a state where the voltage to be applied to the pump is maintained at the diagnostic voltage, and by making a comparison between the diagnostic parameter and a predetermined threshold value, the abnormality diagnosis is carried out by using the diagnostic parameter or the predetermined threshold value which is corrected based on the pump discharge capacity of the pump.

Abstract: A system according to the present disclosure includes a pressure sensor and an engine state module. The pressure sensor is configured to measure pressure in an exhaust gas supply line that supplies exhaust gas from an engine to an emissions measurement system. The emissions measurement system includes a dilution tunnel, a sample probe, and a sample collector. The exhaust gas is diluted with a dilution gas in the dilution tunnel, and the sample probe supplies a portion of the diluted exhaust gas to the sample collector. The engine state module is configured to determine whether the engine is on or off based on at least one of (i) a frequency of pulsations in the exhaust gas supply line pressure and (ii) a magnitude of the pulsations in the exhaust gas supply line pressure.

Abstract: In the abnormality diagnosis device which carries out an abnormality diagnosis of the reducing agent adding device by obtaining a diagnostic parameter which is a parameter correlated with an amount of pressure drop in a reducing agent passage in the case where, from a state in which an addition valve has been closed and in which a voltage to be applied to a pump is controlled to a diagnostic voltage so that the pressure in the reducing agent passage becomes a predetermined pressure, the addition valve is made to open in a state where the voltage to be applied to the pump is maintained at the diagnostic voltage, and by making a comparison between the diagnostic parameter and a predetermined threshold value, the abnormality diagnosis is carried out by using the diagnostic parameter or the predetermined threshold value which is corrected based on the pump discharge capacity of the pump.

Abstract: To provide a controller and a control method for an internal combustion engine capable of estimating exhaust gas temperature at any estimation positions of the exhaust pipe with good accuracy by taking into consideration a temperature drop of exhaust gas by heat radiation of the exhaust pipe. A controller for an internal combustion engine is provided with an outlet gas temperature calculator that calculates an outlet gas temperature which is a temperature of exhaust gas at an outlet of a combustion chamber, based on the driving condition; a heat radiation amount calculator that calculates a temperature decrease amount of the exhaust gas by heat radiation of an exhaust pipe from the outlet of the combustion chamber to an estimation position; and an exhaust gas temperature estimation calculator that estimate an exhaust gas temperature at the estimation position by subtracting the temperature decrease amount from the outlet gas temperature.

Abstract: A soot sensing system includes a soot sensor having a first element, and circuitry to an amount of soot accumulated on the element and to control heating of the element in response to the soot accumulation. An electrostatic repelling voltage (ERV) may be applied to a sensor/heater element(s) during a contamination prevention mode (CPM) to repel ash and reduce contamination of the sensor. A pulsed heating voltage (PHV) may be applied to the elements during the CPM and a pulsed ERV may be applied to the elements during the “off” period of the PHV. All voltage to the elements may be turned off during the CPM and the elements may be floating/ground. A PHV may be applied to the elements during the CPM and no voltage may be applied to the elements during the “off” period of the PHV. A heating voltage may be applied to the elements during a CPM corresponding to a cold start.

Abstract: A method includes supplying a first quantity of a first fuel to an engine and supplying a charge including a second fuel and air to the engine. The first fuel is different from the second fuel. The method further includes mixing the first fuel with the charge, supplying a second quantity of the first fuel to the engine, and igniting at least a portion of the first and second fuels in response to supplying the second quantity of the first fuel.

Abstract: A method of monitoring the reductant delivery performance of a selective catalytic reduction component of a vehicle exhaust system, includes operating a diesel exhaust fluid pump until a reductant delivery performance pressure setpoint is reached. Calculating an average pump duty cycle and commanding the calculated pump duty cycle to be used in the open loop control phase. Calculating an initial average pressure. Injecting a controlled diesel exhaust fluid (DEF). Calculating a final average pressure. Calculating a pressure drop ?P and determining if the calculated pressure drop ?P is less than an expected pressure drop calculated as a function of the average pump duty cycle.

Abstract: Provided is a method for detecting abnormality of an after turbo catalyst (ATC) where fuel from a fuel injection device receiving a post injection command from a controller undergoes oxidation reaction in an exhaust pipe and resultant reaction heat heats the exhaust gas, which provides an ATC-entry-side temperature measuring means measuring a temperature on an entry side of ATC to transmit a measured value to the controller and an ATC-downstream-side temperature measuring means measuring a temperature downstream of ATC. The controller, which transmitted the post injection command, determines whether a fuel injection device normally operates if temperature downstream of ATC is not nonelevated to that on the entry side of ATC, and determines that ATC has abnormality if the fuel injection device normally operates.

Abstract: A method for diagnosing NOx sensors in an exhaust aftertreatment system includes suspending reductant dosing in an exhaust aftertreatment system; purging a reductant deposit in a selective catalytic reduction (SCR) system of the exhaust aftertreatment system; adjusting at least one of an ignition timing and an engine speed for an engine to adjust an engine out nitrogen oxide (NOx) amount; receiving measured SCR inlet NOx data from a SCR inlet NOx sensor and measured SCR outlet NOx data from a SCR outlet NOx sensor; determining a phase shift between the measured SCR inlet and SCR outlet NOx data; applying the determined phase shift to the SCR outlet NOx data; and determining a diagnostic feature based on the SCR inlet NOx data and the phase shifted SCR outlet NOx data regarding a state of the SCR inlet and outlet NOx sensors.

Abstract: An exhaust aftertreatment system may include an oxidation catalyst, a soot sensor, a filter and a control module. The oxidation catalyst may be disposed in an exhaust gas passageway and may receive exhaust gas discharged from an engine. The soot sensor may be at least partially disposed in the exhaust gas passageway downstream of the oxidation catalyst. The filter may be disposed in the exhaust gas passageway downstream of the soot sensor. The control module may be in communication with the soot sensor and may determine a face-plugging condition of the oxidation catalyst based on data received from the soot sensor.

Abstract: A soot sensing system includes a soot sensor having a first element, and circuitry to an amount of soot accumulated on the element and to control heating of the element in response to the soot accumulation. An electrostatic repelling voltage (ERV) may be applied to a sensor/heater element(s) during a contamination prevention mode (CPM) to repel ash and reduce contamination of the sensor. A pulsed heating voltage (PHV) may be applied to the elements during the CPM and a pulsed ERV may be applied to the elements during the “off” period of the PHV. All voltage to the elements may be turned off during the CPM and the elements may be floating/ground. A PHV may be applied to the elements during the CPM and no voltage may be applied to the elements during the “off” period of the PHV. A heating voltage may be applied to the elements during a CPM corresponding to a cold start.

Abstract: A method for calculating exhaust gas temperature indirectly at points in or around an engine exhaust after treatment system for use in determining an amount of unburned hydrocarbons resident therein at a given point in time.

Abstract: A method for operating an exhaust gas purification system of a motor vehicle internal combustion engine is disclosed. The system has an SCR catalyst where a reducing agent containing ammonia is metered into the exhaust gas at a predeterminable metering rate which is produced from a base value and an adaptation factor which corrects the base value. A test procedure checks and, if appropriate, adjusts the adaptation factor where a first nitrogen oxide value is compared with a second nitrogen oxide value of the exhaust gas, where the first and the second nitrogen oxide value are determined by the same nitrogen oxide sensor disposed downstream of the SCR catalyst. The first nitrogen oxide value is determined when the metering of the reducing agent is switched off and the second nitrogen oxide value is determined when the reducing agent is metered at a test metering rate which can be predetermined.

Abstract: An exhaust fluid treatment apparatus used to treat exhaust fluid emitted by a combustion engine includes a check of its functionality. A method of monitoring operation of an exhaust fluid treatment apparatus includes comparing a calculated temperature difference with an expected temperature difference associated with combustion of fuel. If the calculated temperature difference is within an acceptable margin of the expected temperature difference, further fuel injection may be permitted. If the calculated temperature difference is outside the acceptable margin of the expected temperature difference, a temperature of the exhaust gas upstream of the exhaust fluid treatment apparatus may be increased.

Abstract: A diagnostic apparatus for an exhaust gas purification apparatus including a selective catalytic reduction NOx catalyst (SCR catalyst) provided in an exhaust passage of an internal combustion engine, a supplying unit supplying ammonia or an ammonia precursor into exhaust gas flowing into the SCR catalyst and a sensor, provided on a downstream side of the SCR catalyst, detecting NOx and ammonia in exhaust gas. The diagnostic apparatus calculates an amount of decline in output of the sensor due to a reaction between NOx and ammonia at the sensor and performs a diagnosis of the supplying unit based on the calculated amount of decline in output of the sensor.

Abstract: An arrangement for operating a sensor, in particular a bridge sensor, comprises a sensor input (Vin1, Vin2) for connecting the sensor (Brdg) and a clocked signal generator (Osc), which is coupled to the sensor input (Vin1, Vin2). Furthermore an amplifier (Amp) is provided for detecting sensor signals (Sn, Sn+1), which is connected on the input side to a signal input (IN+, IN?) for connecting the sensor (Brdg), wherein the detection takes place depending on the clock pulse of the signal generator (Osc). A signal processing device (PROC) is connected to an output (AOUT+, AOUT?) of the amplifier (Amp) and is arranged to demodulate the sensor signals (Sn, Sn+1) that follow one another according to the clock pulse.

Abstract: It is intended to display a schematic diagram of substantially the whole of an internal combustion engine test system on a screen and a color, brightness, pattern or shape of a symbol representing a test device shown in the schematic diagram are changed according to a degree of operation safety of the test device, whereby a user is allowed to intuitively recognize a situation relating to the safety of the entire system at a glance.

Abstract: An exhaust gas treatment system for an internal combustion engine may have a reductant delivery system with a controller that performs period diagnostics to determine whether there is a blockage in the reductant delivery system. The diagnostic procedure may include sampling first and second pressures at first and second operating conditions, respectively, and then comparing the first pressure differential between the first and second pressures with one or more threshold pressure differentials to determine whether system components such as a dosing line and an injector are at least partially blocked. If such a test is not conclusive, it may be repeated at a third and fourth operating conditions to provide a second pressure differential. The offset between the first and second pressure differentials may also be used to help diagnose where a blockage in the system resides.

Abstract: The present invention is adapted to be provided with: a first sampling line for sampling raw exhaust gas; a first concentration measuring part that measures the concentration of the predetermined target component contained in the raw exhaust gas; a second sampling line for sampling diluted exhaust gas; a second concentration measuring part that measures the concentration of the target component contained in the diluted exhaust gas; and an arithmetic unit that, with use of first measured concentration, second measured concentration, and a diluted exhaust gas flow rate, calculates a raw exhaust gas flow rate, wherein in a state where the first sampling line and the first concentration measuring part are heated, the first concentration measuring part measures the concentration of the target component contained in the raw exhaust gas.

Abstract: For a method for determining the concentration of aerosols in hot gases, particularly in exhaust gases of internal combustion engines, the removal of volatile and semi-volatile particles by heating the exhaust gas is provided, as well as the measurement of the concentration of the aerosols, optionally in a partial flow of an optionally diluted exhaust gas flow. In order to enable precise measurements of the aerosol concentration in the exhaust gas with lower energy consumption, the exhaust gas is divided in a first stage into two partial flows, both of which are heated, with one of the partial flows being filtered at least once, preferably before heating, and the two partial flows are subsequently recombined. In a second stage, the exhaust gas is again divided into two partial flows, with one of the partial flows being heated even further than in the first stage, and with the other partial flow being filtered at least once.

Abstract: A system and method is provided for synchronizing a first and second signal of an exhaust sampling system. The first signal is generated by a first instrument and includes an exhaust flow rate component and a first instrument time stamp component. The second signal is generated by a second instrument and includes a pollutant concentration component and a second instrument time stamp component. The second instrument also generates a tertiary signal that has been influenced by the first signal and includes a second instrument time stamp component. A synchronization module determines a time relationship for synchronizing the first signal and the second signal by comparing the first flow rate component and the first instrument time stamp component of the first signal to the tertiary signal and the second instrument time stamp component of the tertiary signal. The synchronization provides accurate calculation of a pollutant mass flow rate.

Abstract: Methods and systems for controlling and/or diagnosing an emission control system of a vehicle having a first SCR region upstream of a second SCR region are provided herein. One exemplary method includes, indicating degradation based on a first SCR region performance during a first condition; and indicating degradation based on a second SCR region performance during a second condition, the first condition different than the second condition. In this way, different levels of degradation among different SCR regions may be used to indicate emissions levels have increased above a threshold value, for example.

Abstract: An operation control system for a solenoid valve of a combustion engine having at least one solenoid valve to hydraulically couple and decouple actuation forces of a cam with a gas valve of a cylinder. A driving unit operates the solenoid valve, and a first detection device monitors a status of the solenoid valve by supplying a status signal to a control unit during an engine intake cycle phase of the cylinder. A second detection device analyzing a system parameter corresponding to the cylinder and supplying a control signal during an engine cycle phase other than the engine intake cycle phase. The control unit delays the status signal based on the status signal to temporally synchronize the status signal with the control signal, or a secondary control signal based thereon, and compares the status signal with the control signal or the secondary signals with each other using an AND-Function.

Abstract: A method for an exhaust-gas aftertreatment system which is operated on an internal combustion engine operated with an excess of air, in which exhaust-gas aftertreatment system soot particles are separated out of exhaust gas by a particle filter and the particle filter is regenerated with the aid of NO2 formed on an NO oxidation catalytic converter mounted upstream of the particle filter. A reduction of the nitrogen oxides is realized by a reducing agent which splits to form ammonia being metered into the exhaust-gas flow upstream of the particle filter and the particle filter is laden with a catalytically active material for the selective catalytic reduction of nitrogen oxides. The NH3 to NOx ratio (feed ratio ?) is varied in phases by changing the nitrogen oxide untreated emissions and/or the supplied amount of reducing agent, in such a way that the feed ratio ? alternates in phases between values of greater than one and values of less than one.

Abstract: Various methods are provided for diagnosing an exhaust fluid sensor disposed in an exhaust fluid passage. By monitoring the sensor during conditions when it is in contact with the exhaust fluid and when it is not in contact with the exhaust fluid, an expected change in the sensor output can be monitored to identify whether the sensor is generating sufficiently accurate readings.

Abstract: A method for the operational test measurement of a lambda probe, particularly for the purpose of calibrating and/or determining the status of the lambda probe, wherein pure air is circulated around a probe head of the lambda probe is disclosed. The method has the following steps:, —insertion of the lambda probe into a flow receptacle which is separate from an engine construction, in such a manner that an air stream (L) can be circulated around the probe head; generation of an air stream (L) in the flow receptacle; evaluation of probe measurement signals (S), wherein a calibration value is obtained and/or a heating current of the lambda probe is evaluated. A device for carrying out the method, as well as a system, is also disclosed herein.

Abstract: A method performs a diagnosis of a lambda sensor of a “UEGO” type of an exhaust system for an internal-combustion engine. The lambda sensor includes a series of pins. The diagnosis method comprises steps of: heating the lambda sensor to cause the lambda sensor to reach an inner temperature that is higher than about 600° C.; polarizing a first one of the pins by connecting the first pin to a supply voltage through a first limiting resistance; measuring a voltage of all of the pins while the first pin is connected to the supply voltage; and diagnosing a presence of a short circuit to an electrical ground if the voltage of at least one of the pins is lower than a predetermined threshold. A control unit performs the diagnosis.

Abstract: A deposit detection device for an exhaust pump is provided, which can be easily put into operation without the burdens of, for example, installing equipment for flowing a gas, or adding or changing operation modes in apparatuses.

Abstract: The disclosure relates to a method and an observer for determining the exhaust manifold temperature in a turbocharged engine upstream of the turbine. In one example, a method for determining an exhaust manifold temperature in a turbocharged engine, the engine including a turbocharger and a turbine and the exhaust manifold temperature including a temperature upstream of the turbine, the method comprises estimating a value of the exhaust manifold temperature based on a model, measuring a temperature downstream of the turbine, and correcting the value of the exhaust manifold temperature based on the measurement.

Abstract: System, apparatus, and methods are disclosed for enabling a quality diagnostic of an aqueous urea solution (AUS) of an exhaust system when the AUS is outgassed. Systems, apparatus, and methods are also disclosed for disabling an output of a quality condition of the AUS in response at least in part to detecting that an AUS fill event of an AUS storage tank has occurred.

Abstract: An apparatus for on-board diagnoses of causes of NOX conversion efficiency degradation including: a diagnosis exhaust-pipe fuel injection control unit; a NOX purification device failure specifying unit; and an oxidizing catalyst device failure specifying unit.

Abstract: A diesel particulate filter (“DPF”) system is provided with temperature sensors at an entrance side and an exit side of a diesel oxidation catalyst, an SV ratio determining device that determines an exhaust gas SV ratio by measuring flow rate of exhaust gas during the DPF forcible regeneration, and an injector diagnosing device including a heat-generation region determining unit to which detection values of the temperature sensors and a determination value of the SV ratio determining device are input to determine whether or not these values are within a theoretical heat-generation region, and an actual injection amount diagnosing unit that diagnoses a decrease amount in an actual injection amount of an exhaust pipe injector, when the detection values of the temperature sensors and the determination value of the SV ratio determining device are within the theoretical heat-generation region.

Abstract: A competence diagnosis system for a urea water temperature sensor that can prevent a misdiagnosis when urea water is replenished in a urea tank. The system includes a urea water level condition determination unit that stores a urea water level, which is measured by a level sensor provided in the urea tank, in a storage unit immediately before key-off, obtains a level difference between the urea water level stored in the storage unit and a current urea water level after key-on, and allows a diagnosis by the competence diagnosis unit through temperature comparison when the level difference is less than or equal to a predetermined threshold value.

Abstract: The present invention relates to an exhaust sensor (1) comprising a tubular support body (2) receiving a measurement probe (3), a first end of said probe extending beyond a first end of the tubular support body through an opening therein, and a second end of said probe being secured to an electrical connection connector (4) housed inside the tubular support body (2) and fitting closely against its walls. According to the invention, the measurement probe is sealed inside the tubular support body (2) and is thermally decoupled from the environment outside the tubular support body by means of an assembly of spacers (10, 11, 12, 13) made of ceramic and of glass, the spacers being threaded around the measurement probe and distributed inside the tubular support body between the electrical connection connector and the first end of the tubular support body so as to provide at least two separate cavities, said spacers providing leaktight sealing between the measurement probe and the tubular support body.

Abstract: A system for taking exhaust gas samples from internal combustion engines includes an exhaust gas duct comprising an outflow cross section and an exhaust gas inlet. The exhaust gas duct communicates with an exhaust gas source via the exhaust gas inlet. An air duct takes in ambient air via a filter. The outflow cross section is concentric in the air duct. A mixing zone is arranged downstream of the outflow cross section. A dilution tunnel has an exhaust gas/air mixture flow therethrough. An annular orifice is arranged downstream of the outflow cross section in the dilution tunnel. A flow deflection device is arranged upstream of the annular orifice and downstream of the outflow cross section. The flow deflection device deflects the exhaust gas/air mixture so that it departs from a center axis of the dilution tunnel immediately downstream of the flow deflection device in an axially symmetrical manner.

Abstract: Methods are provided for determining an exhaust fluid level in an exhaust fluid storage tank based on a signal, and a quality of the signal from an exhaust fluid level sensor located in the exhaust fluid tank of a vehicle.

Abstract: An exhaust aftertreatment system includes an exhaust aftertreatment component housing and a sensor table coupled to an exterior surface of the exhaust aftertreatment component housing. The sensor table includes a base including footings and a first platform offset from the footings by first standoffs so to define a first air gap. The base also includes second standoffs extending from the first platform. The sensor table also includes a top plate including a second platform and third standoffs extending from the second platform. The second platform is fixedly coupled to the second standoffs so to define a second air gap between the first platform and the second platform. The sensor table further includes a first sensor module coupled to the third standoffs so to define a third air gap between the second platform and the first sensor module.

Abstract: Air required for measurement of exhaust gas components is supplied to an exhaust sensor without using a device for generating positive pressure. In a structure for arrangement, in an engine (1), of an exhaust sensor (10) that measures exhaust gas components and requires air for the measurement of the exhaust gas components, an exhaust pipe (5) of the engine (1) communicates with the exhaust sensor (10) through an introduction pipe (15), the exhaust sensor (10) communicates with an intake pipe (2) of the engine (1) through a discharge pipe (16), and an atmosphere pipe (17) open to the atmosphere is connected to the exhaust sensor (10), so that exhaust gas is sucked into the exhaust sensor (10) through the introduction pipe (15) while air is sucked into the exhaust sensor (10) through the atmosphere pipe (17) due to intake negative pressure generated during an intake stroke of the engine (1).

Abstract: The invention relates to a method for monitoring a sensor unit (20) that is arranged in the exhaust gas region of an internal combustion engine (10). According to the invention, a sensor temperature (31, 32) is directly or indirectly determined by the sensor unit (20), and is compared to an exhaust temperature (33) that is determined by a further sensor unit and/or to model variables and/or to defined threshold values, whereby a dismounting and/or an inappropriate mounting of the sensor unit is indicated.

Abstract: An engine diagnostic tool includes a diagnostic engine calibration module structured to include a plurality of diagnostic processes for operating an internal combustion engine system of an immobilized vehicle. One or more of the plurality of diagnostic processes are structured to be an intrusive diagnostic process for the internal combustion engine system, wherein the intrusive diagnostic process causes the internal combustion engine system to operate outside of one or more calibration parameters. The diagnostic engine module is further structured to control the order and timing of each diagnostic process in the plurality of diagnostic processes.

Abstract: The present invention relates to a method for measuring the content of at least one compound in an exhaust gas stream resulting from internal combustion. A first relative proportion of a first compound in the exhaust gas stream is measured by means of a first sensor, and a defined flow of a first gas is added to said exhaust gas stream downstream said first sensor. A second relative proportion of said first compound in the combined stream of said exhaust gas stream and said added gas is measured by means of a second sensor, and a mass flow of said first compound in said exhaust gas stream resulting from said combustion in said internal combustion is determined by means of said first and second relative proportions and said defined flow of said first gas. The invention also relates to a system and vehicle dynamometer.

Abstract: A protector (100) of a gas sensor (1) includes an inner protector (120) and an outer protector (110). The inner protector accommodates a gas sensor element (10) and has a tubular side wall (122) having inner gas introduction holes (130), and a bottom wall (124). The outer protector has a tubular side wall (112) having outer gas introduction holes (115), a frustum-like taper wall (117) tapering frontward and an outer gas discharge hole (170) formed inside a front end edge (117s) of the taper wall. When SL represents an area defined by the front end edge of the taper wall, the area S of the opening of the outer gas discharge hole satisfies the relational expression ½×SL?S?SL. A cover portion (127) and a bottom wall (124) are partially away from each other along the axial direction, thereby forming side openings (162).

Abstract: A method for testing the evaporative emission system of a vehicle. The method provides for testing the evaporative emission system of a vehicle having a forced induction engine. The method includes controlling a vacuum bypass valve and a purge flow control valve to create the necessary conditions to perform the testing of the evaporative emission system.

Abstract: A diagnostic method and system is described for diagnosing an operating condition of a conductive particulate matter sensor. The sensor has a substrate with electrical resistance that varies with temperature and two electrodes on the substrate adapted to collect particulate matter between the electrodes, thereby establishing an electrically conductive path through collected particulate matter between the electrodes that can be detected by measuring electrical resistance between the electrodes, Relect. The diagnosis is performed by heating the substrate in the area between the electrodes and using the resistance between the electrodes to determine detecting whether contamination is present on the surface of the sensor. Heat may be maintained on the sensor to attempt to burn off a detected contaminant, and a subsequent resistance reading may be used to determine if the contaminant was successfully burned off.

Abstract: Methods and apparatus for detecting the filtering state of a filter, such as a particulate filter. Some embodiments include one or more capacitive sensors that provide a signal corresponding to the filtered state of the filter with a change in measured capacitance. A novel ECT based sensing technique for soot load estimation in a diesel particulate filter is presented. The sensing technology is based on principle that deposited soot thickness inside DPF causes a variation in the dielectric constant which has a direct impact on the capacitance of ECT system and its output voltage. The sensor can be built into the DPF outer shell as indicated in the design. The simulation results demonstrate that there is a direct relationship between the amount of soot load in the DPF and the output voltage of the ECT system which can be used to estimate the soot load.

Abstract: 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.

Abstract: The present invention relates to an exhaust sensor (1) comprising a tubular support body (2) receiving a measurement probe (3), a first end of said probe extending beyond a first end of the tubular support body through an opening therein, and a second end of said probe being secured to an electrical connection connector (4) housed inside the tubular support body (2) and fitting closely against its walls. According to the invention, the measurement probe is sealed inside the tubular support body (2) and is thermally decoupled from the environment outside the tubular support body by means of an assembly of spacers (10, 11, 12, 13) made of ceramic and of glass, the spacers being threaded around the measurement probe and distributed inside the tubular support body between the electrical connection connector and the first end of the tubular support body so as to provide at least two separate cavities, said spacers providing leaktight sealing between the measurement probe and the tubular support body.