Abstract: Methods and systems are provided for monitoring a NOx storage capacity of a passive NOx adsorption catalyst (PNA) included in an exhaust gas after-treatment system of an engine. In one example, a method may include, after an engine cold start and prior to an exhaust gas temperature reaching an upper threshold temperature, indicating degradation of the PNA based on an amount of NOx measured downstream of the PNA during a fuel cut event and while the exhaust gas temperature is between a lower threshold temperature and the upper threshold temperature. In this way, degradation of the NOx storage capacity may be inferred based on an amount of NOx released from the PNA and independent of a NOx storage measurement.

Abstract: Methods and systems are provided for monitoring a NOx storage capacity of a passive NOx adsorption catalyst (PNA) included in an exhaust gas after-treatment system of an engine. In one example, a method may include, after an engine cold start and prior to an exhaust gas temperature reaching an upper threshold temperature, indicating degradation of the PNA based on an amount of NOx measured downstream of the PNA during a fuel cut event and while the exhaust gas temperature is between a lower threshold temperature and the upper threshold temperature. In this way, degradation of the NOx storage capacity may be inferred based on an amount of NOx released from the PNA and independent of a NOx storage measurement.

Abstract: Methods and systems for operating an engine with an electrically driven compressor are described. In one example, output of the electrically driven compressor is adjusted to increase a temperature of an engine so that the engine may be started without glow plugs or with glow plugs that have a lower heat capacity output. Additionally, a position of a recirculation valve may be adjusted to increase the temperature of the engine.

Abstract: Methods and systems for operating an engine with an electrically driven compressor are described. In one example, output of the electrically driven compressor is adjusted to increase a temperature of an engine so that the engine may be started without glow plugs or with glow plugs that have a lower heat capacity output. Additionally, a position of a recirculation valve may be adjusted to increase the temperature of the engine.

Abstract: In one example, a method of operating an engine having a diesel particulate filter in a vehicle, the particulate filter having a length and depth, includes performing particulate filter regeneration in response to temperature variation across the length and/or depth of the particulate filter.

Abstract: In one example, a method of operating an engine having a diesel particulate filter in a vehicle, the particulate filter having a length and depth, includes performing particulate filter regeneration in response to temperature variation across the length and/or depth of the particulate filter.

Abstract: A method of operating an engine having a diesel particulate filter in a vehicle is disclosed. In one example, the filter is regenerated in response to a temperature differential across each of a plurality of filter channels. The method can improve the timing of filter regeneration.

Abstract: A method for improving engine control during a regeneration of an exhaust gas after treatment device is described. According to one aspect of the description, engine air amount and engine fuel amount may be adjusted based on data from a previously executed regeneration of an exhaust gas after treatment device.

Abstract: Feedback control of an internal combustion engine is performed based on a signal from a vibration sensor and a crankshaft angle sensor. An energy factor can be computed based on these sensor signals. A vector of energy factor can be computed as a function of crank angle degree over a particular window of engine rotation of interest. Based on the energy factor vector, combustion phasing can be estimated.

Abstract: In one example, a method of operating an engine having a diesel particulate filter in a vehicle, the particulate filter having a length and depth, includes performing particulate filter regeneration in response to temperature variation across the length and/or depth of the particulate filter.

Abstract: The invention relates to a method of performing feedback control of the operation of an internal combustion engine based on a signal from a vibration sensor and a crankshaft angle sensor. An energy factor can be computed based on these sensor signals which provides an estimate of the combustion phasing and combustion intensity. A vector of energy factors can be computed as a function of crank angle degree over a particular window of engine rotation of interest. Based on the energy factor vector, combustion phasing can be estimated.

Abstract: In an apparatus having an internal combustion engine, an exhaust system for transporting engine exhaust from the engine, a particulate filter disposed in the exhaust system, and a particulate detector disposed downstream of the particulate filter in the exhaust system, a method for monitoring a performance characteristic of the particulate filter, including detecting an increase in exhaust flow in the exhaust system; determining if the increase in the exhaust flow occurs at a rate equal to or greater than a threshold rate of change; and if the increase in the exhaust flow is determined to have occurred at a rate equal to or greater than the threshold rate of change, then determining from a signal received from the particulate detector if a value of a parameter related to particulate matter passing through the particulate filter has a predetermined relationship to a predetermined threshold value that indicates a reduction in filter trapping efficiency.

Abstract: An apparatus comprising an internal combustion engine, an exhaust system in communication with the engine, a particulate sensor associated with the exhaust system, and a controller in electrical communication with the particulate sensor, wherein the controller is configured to determine a change in a rate of exhaust flow in the exhaust system, to compare the change in the rate of exhaust flow to a preselected threshold rate of change; and if the change in the rate of exhaust flow has a preselected relationship to the preselected threshold rate of change, then to determine a degradation of the sensor.

Abstract: A system for a diesel engine having an intake manifold and an exhaust manifold, comprises a turbocharger between the intake and exhaust manifolds of the engine; a low pressure exhaust gas recirculation system with a first end coupled to the exhaust manifold downstream of the turbocharger and a second end couple to the intake manifold upstream of the turbocharger, said low pressure exhaust gas recirculation having a first valve coupled thereto for regulating flow; a high pressure exhaust gas recirculation system with a first end coupled to the exhaust manifold upstream of the turbocharger and a second end coupled to the intake manifold downstream of the turbocharger, said high pressure exhaust gas recirculation having a second valve coupled thereto for regulating flow; a first mass airflow sensor coupled in the engine intake manifold upstream of an inlet of said second end of said low pressure exhaust gas recirculation system; and a control system configured to diagnose the degradation of said first mass airfl

Abstract: A system for a diesel engine having an intake manifold and an exhaust manifold, comprising a turbocharger coupled between the intake and exhaust manifolds of the engine; a low pressure exhaust gas recirculation system with a first end coupled to the exhaust manifold downstream of the turbocharger and a second end coupled to the intake manifold upstream of the turbocharger, said low pressure exhaust gas recirculation having a first valve coupled thereto for regulating flow; a high pressure exhaust gas recirculation system with a first end coupled to the exhaust manifold upstream of the turbocharger and a second end coupled to the intake manifold downstream of the turbocharger, said high pressure exhaust gas recirculation having a second valve coupled thereto for regulating flow; a first mass airflow sensor coupled in the engine intake manifold upstream of said second end of said low pressure exhaust gas recirculation system; a second mass airflow sensor coupled in the engine intake manifold downstream of said

Abstract: A method and system for controlling regeneration in a particulate filter coupled to an internal combustion engine. The method controls hydrocarbon injection into engine exhaust upstream of an oxidation catalyst disposed upstream of the particulate filter in accordance an algebraic sum of a feedforward term and a feedback term. The feedforward term is a function of a difference between with the engine exhaust temperature upstream of the catalyst and a predetermined desired particulate filter temperature. The feedback term is a function of a temperature of the particulate filter and the predetermined desired particulate filter temperature.

Abstract: A low cost particulate filter pressure monitoring system and method are presented. The differential pressure across the filter is estimated based on an atmospheric pressure, a measured absolute exhaust gas pressure upstream of the first emission control device coupled to the engine and an estimated pressure drop across all other emission control devices.

Abstract: An accurate thermodynamic model of an Active Lean NOx (ALNC) Catalyst is presented. The model takes into account hydrocarbon storage and release mechanisms of the ALNC, as well as the degradation in the ALNC hydrocarbon conversion efficiency due to ageing, and thus provides a more accurate estimate of an exotherm generated by hydrocarbon combustion in the ALNC. The estimated exotherm can them be used to detect system degradation and identify components responsible for the degradation.

Abstract: An accurate thermodynamic model of an Active Lean NOx (ALNC) Catalyst is presented. The model takes into account hydrocarbon storage and release mechanisms of the ALNC, as well as the degradation in the ALNC hydrocarbon conversion efficiency due to ageing, and thus provides a more accurate estimate of an exotherm generated by hydrocarbon combustion in the ALNC. The estimated exotherm can them be used to detect system degradation and identify components responsible for the degradation.

Abstract: A method and system for simultaneously regenerating a particulate filter coupled to an internal combustion engine and for desulfating a lean NOx trap disposed downstream of the particulate filter. The method includes adjusting at least one engine operating parameter to maintain a desired air fuel ratio for gases exiting the particulate filter in accordance with a difference between a reference set point air fuel ratio level and the air fuel ratio of gases exiting the particulate filter and wherein the reference set point level is changed between a rich air fuel ratio and a lean air fuel ratio as a function of the air fuel ratio of the gases exiting the lean NOx trap.