Abstract: A system is provided for diagnosing operation of an exhaust gas aftertreatment component for an internal combustion engine. The system includes a NOx sensor producing a NOx signal indicative of NOx content of exhaust gas exiting the aftertreatment component, and a control circuit configured to estimate as a function of a number of engine operating conditions a NOx inlet content corresponding to a NOx content of exhaust gas produced by the engine and entering the aftertreatment component. The control circuit is configured to determine a NOx conversion efficiency of the aftertreatment component as a function of the NOx signal and of the NOx inlet content, and to determine that the aftertreatment component is degraded if the NOx conversion efficiency is below a threshold value for at least a first predefined time period.

Abstract: An engine exhaust treatment system using a control system is described. In one form of the present invention, engine exhaust gas contaminates are passed through a selective reduction catalyst and a contaminate reducing agent is injected into the catalyst. The amount of contaminates present in the exhaust proximate to the selective reduction catalyst are sensed using at least one sensor. In one embodiment, input signals are sent to a control system from the sensor or sensors and a feedforward control combined with a feedback loop is used to transform these signals and a predetermined catalyst output contaminate value into an output signal. The output signal instructs a provider to inject contaminate reducing agents in a manner to efficiently track the desired predetermined catalyst output contaminate value.

Abstract: A system is provided for regenerating an exhaust gas aftertreatment component of an internal combustion engine. The system is operable to determine an output torque of the engine, and to supply a single quantity of fuel to the engine after combustion of a main quantity of fuel if the output torque is greater than a torque threshold, and to otherwise supply a first quantity of fuel to the engine near an end of combustion of the main quantity of fuel followed by supplying a second quantity of fuel after combustion of the main quantity of fuel.

Abstract: A system is provided for regenerating an exhaust gas aftertreatment component of an internal combustion engine. The system is operable to determine an output torque of the engine, and to supply a single quantity of fuel to the engine after combustion of a main quantity of fuel if the output torque is greater than a torque threshold, and to otherwise supply a first quantity of fuel to the engine near an end of combustion of the main quantity of fuel followed by supplying a second quantity of fuel after combustion of the main quantity of fuel.

Abstract: A system is provided for diagnosing operation of an exhaust gas aftertreatment component for an internal combustion engine. The system includes a NOx sensor producing a NOx signal indicative of NOx content of exhaust gas exiting the aftertreatment component, and a control circuit configured to estimate as a function of a number of engine operating conditions a NOx inlet content corresponding to a NOx content of exhaust gas produced by the engine and entering the aftertreatment component. The control circuit is configured to determine a NOx conversion efficiency of the aftertreatment component as a function of the NOx signal and of the NOx inlet content, and to determine that the aftertreatment component is degraded if the NOx conversion efficiency is below a threshold value for at least a first predefined time period.

Abstract: An engine exhaust treatment system using a control system is described. In one form of the present invention, engine exhaust gas contaminates are passed through a selective reduction catalyst and a contaminate reducing agent is injected into the catalyst. The amount of contaminates present in the exhaust proximate to the selective reduction catalyst are sensed using at least one sensor. In one embodiment, input signals are sent to a control system from the sensor or sensors and a feedforward control combined with a feedback loop is used to transform these signals and a predetermined catalyst output contaminate value into an output signal. The output signal instructs a provider to inject contaminate reducing agents in a manner to efficiently track the desired predetermined catalyst output contaminate value.