Abstract: Methods and systems are provided for controlling a catalyst temperature. In one example, a method includes throttling in response to the catalyst temperature exceeding a threshold temperature. The throttling includes adjusting an intake throttle position to a more closed position. The throttling further includes increasing a turbine work extraction via adjusting a position of a plurality of turbine vanes to decrease a turbine outlet temperature.

Abstract: Methods and systems for operating an engine that includes a low pressure EGR passage and a selective reduction catalyst are disclosed. In one example, an actuator is adjusted in response to a NOx mass flow rate in the low pressure EGR passage.

Abstract: Methods and systems for increasing fuel economy of a vehicle including a SCR catalyst are presented. In one example, an amount of EGR provided to an engine is decreased in response to performance of the SCR being within a predetermined range of performance. The methods and systems may increase vehicle fuel economy while vehicle tailpipe emissions are achieved.

Abstract: Methods and systems for operating an engine that includes a low pressure EGR passage and a selective reduction catalyst are disclosed. In one example, an actuator is adjusted in response to a NOx mass flow rate in the low pressure EGR passage.

Abstract: Methods and systems for operating an engine that includes a low pressure EGR passage and a selective reduction catalyst are disclosed. In one example, an actuator is adjusted in response to a NOx mass flow rate in the low pressure EGR passage.

Abstract: Methods and systems for operating an engine that includes a low pressure EGR passage and a selective reduction catalyst are disclosed. In one example, an actuator is adjusted in response to a NOx mass flow rate in the low pressure EGR passage.

Abstract: Methods and systems for increasing fuel economy of a vehicle including a SCR catalyst are presented. In one example, an amount of EGR provided to an engine is decreased in response to performance of the SCR being within a predetermined range of performance. The methods and systems may increase vehicle fuel economy while vehicle tailpipe emissions are achieved.

Abstract: A vehicle and method are provided that determine a misfire torque limit for an engine in the vehicle. The vehicle includes an electric machine operable to provide torque to the engine. The method includes commanding the engine to operate at a predetermined torque and a predetermined speed, thereby putting the engine in an idle state. An output torque of the engine is then determined while the engine is in the idle state. A torque offset, defined as the difference between the torque command and the determined engine output torque, is also determined. The misfire torque limit for the engine is then determined based at least in part on the torque offset.

Abstract: A vehicle and method are provided that determine a misfire torque limit for an engine in the vehicle. The vehicle includes an electric machine operable to provide torque to the engine. The method includes commanding the engine to operate at a predetermined torque and a predetermined speed, thereby putting the engine in an idle state. An output torque of the engine is then determined while the engine is in the idle state. A torque offset, defined as the difference between the torque command and the determined engine output torque, is also determined. The misfire torque limit for the engine is then determined based at least in part on the torque offset.