Abstract: A method of regeneration of an emission control device in a diesel engine of a vehicle having a wheel brake comprises receiving a generation request by an operator of the vehicle; activating the wheel brake; increasing engine torque; and regenerating the emission control device.

Abstract: A method are presented for monitoring an amount of ammonia stored in a urea-based SCR catalyst based on a response of a sensor coupled downstream of the catalyst to a periodic desorbtion of a small amount of ammonia. The sensor could be an ammonia sensor, or a NOx sensor whose signal is sensitive to presence of both NOx and ammonia. The method can be performed at engine start to establish initial ammonia storage amount, or, alternatively, to adjust ammonia storage amounts or diagnose degradation when NOx conversion efficiency of the catalyst is below a predetermined value.

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: 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 for diagnosing degradation in a pair of NOx sensors coupled upstream and downstream of a NOx catalyst is presented. The method is performed when catalyst temperature is such that its NOx conversion efficiency is substantially zero, such as when the catalyst temperature is very low (at cold start) or very high (e.g., following regeneration). Under those conditions, sensor degradation can be diagnosed if the upstream and downstream NOx sensor readings are not substantially the same.

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: 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 lean NOx trap in accordance with a difference between a reference set point air fuel ratio level and the air fuel ratio of gases exiting the lean NOx trap 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 exiting the lean NOx trap.

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.