Abstract: An emissions control system for a motor vehicle including an internal combustion engine includes a lean NOx trap (LNT) device including an LNT inlet and an LNT outlet, and a LNT sensor arranged at the LNT inlet. The LNT sensor is operable to detect a temperature of exhaust gases passing into the LNT device. A selective catalytic reduction (SCR) member is fluidically connected to the LNT device. The SCR device includes an SCR inlet and an SCR outlet. An SCR sensor is mounted to the SCR. The SCR sensor is operable to detect a temperature of the SCR. A LNT regeneration control system including a LNT regeneration controller is operatively connected to the LNT sensor and the SCR sensor. The LNT regeneration control system is operable to activate the LNT regeneration controller based on inputs from the LNT sensor and the SCR sensor.

Abstract: An internal combustion engine is coupled to an oxidation catalyst disposed upstream of a second catalytic device. A controller includes an instruction set executable to detect a cold start engine starting event, monitor first and second temperature sensors, control each of the fuel injectors to execute a first set of fuel injection events for each cylinder event in response to an output torque request, and execute a second set of fuel injection events for each cylinder event after cylinder top-dead-center. The second set of fuel injection events includes a final injection event, and a duration of the final injection event is determined based upon the first and second temperatures.

Abstract: A method for engine-out soot flow rate prediction of an exhaust gas treatment system is provided. A measured level of oxides of nitrogen in the exhaust gas treatment system is received. An engine fuel injection timing and air-fuel ratio of an engine producing the oxides of nitrogen are also received. An engine timing factor is determined based on the engine fuel injection timing. An engine air-fuel ratio factor is determined based on the engine air-fuel ratio. An engine-out soot flow rate prediction is generated based on the measured level of oxides of nitrogen, the engine timing factor, and the engine air-fuel ratio factor.

Abstract: An internal combustion engine is configured to operate in a compression-ignition combustion mode and includes an exhaust aftertreatment system having an ammonia-selective catalytic reduction device. A method for operating the engine includes determining a present engine NOx generation rate, determining a NOx reduction rate of the ammonia-selective catalytic reduction device, determining an ammonia slip rate from the ammonia-selective catalytic reduction device corresponding to the NOx reduction rate of the ammonia-selective catalytic reduction device and the present engine NOx generation rate, and controlling engine operation to adjust the present engine NOx generation rate in response to the ammonia slip rate from the ammonia-selective catalytic reduction device.

Abstract: A method for engine-out soot flow rate prediction of an exhaust gas treatment system is provided. A measured level of oxides of nitrogen in the exhaust gas treatment system is received. An engine fuel injection timing and air-fuel ratio of an engine producing the oxides of nitrogen are also received. An engine timing factor is determined based on the engine fuel injection timing. An engine air-fuel ratio factor is determined based on the engine air-fuel ratio. An engine-out soot flow rate prediction is generated based on the measured level of oxides of nitrogen, the engine timing factor, and the engine air-fuel ratio factor.

Abstract: An internal combustion engine is configured to operate in a compression-ignition combustion mode and includes an exhaust aftertreatment system having an ammonia-selective catalytic reduction device. A method for operating the engine includes determining a present engine NOx generation rate, determining a NOx reduction rate of the ammonia-selective catalytic reduction device, determining an ammonia slip rate from the ammonia-selective catalytic reduction device corresponding to the NOx reduction rate of the ammonia-selective catalytic reduction device and the present engine NOx generation rate, and controlling engine operation to adjust the present engine NOx generation rate in response to the ammonia slip rate from the ammonia-selective catalytic reduction device.