Abstract: Methods and systems are provided for maintaining efficiency of a catalyst that is positioned in an exhaust system downstream of an internal combustion engine. In one example, the catalyst may be heated via supplying fuel to a cylinder that does not combust the fuel. The fuel may be oxidized at the catalyst via excess oxygen in the exhaust system.

Abstract: Methods and systems are provided for maintaining efficiency of a catalyst that is positioned in an exhaust system downstream of an internal combustion engine. In one example, the catalyst may be heated via supplying fuel to a cylinder that does not combust the fuel. The fuel may be oxidized at the catalyst via excess oxygen in the exhaust system.

Abstract: Systems and methods for operating an engine that is started via expansion stroke combustion are described. In one example, the method increases air flow through the engine during an engine stopping process so that a larger amount of air may be trapped in a cylinder that is on its expansion stroke so that greater amounts of engine torque may be provided during engine starting.

Abstract: Systems and methods for preparing an engine for a cold start are described. In one example, the air is injected into one or more pre-chambers of engine cylinders in response to an engine start request so that one or more cylinders may be heated before the engine is started. The engine may or may not be rotated while air is being injected to pre-chambers of engine cylinders.

Abstract: Systems and methods for operating an engine that is started via expansion stroke combustion are described. In one example, the method increases air flow through the engine during an engine stopping process so that a larger amount of air may be trapped in a cylinder that is on its expansion stroke so that greater amounts of engine torque may be provided during engine starting.

Abstract: Systems and methods for stopping an engine of a vehicle are described. In one example, the method anticipates when an engine is expected to stop and modifies engine operation so that less fuel is in the engine's intake ports when the engine is stopped so that the fuel may not escape the engine when the engine is restarted.

Abstract: Systems and methods for starting an engine of a hybrid vehicle are described. In one example, the method uses the engine to generate larger amounts of thermal energy while the engine is rotated under power of an electric machine. The systems and methods described herein may be applied to series and parallel hybrid vehicles.

Abstract: A method for operating an engine during a fuel cut-off mode is disclosed. The method may adjust exhaust valve opening timing and exhaust valve lift of one or more cylinders to heat air flowing through the one or more cylinders so that a temperature of an after treatment device may be maintained or increased.

Abstract: Systems and methods for starting an engine of a hybrid vehicle are described. In one example, the method uses the engine to generate larger amounts of thermal energy while the engine is rotated under power of an electric machine. The systems and methods described herein may be applied to series and parallel hybrid vehicles.

Abstract: Methods and systems are provided for increasing a catalyst temperature prior to entering a vehicle mode where combustion is temporarily discontinued. In one example, a method for increasing a temperature of an emission control device before a transient fuel shut-off (TFSO) event of an engine via a spark timing adjustment and an exhaust valve opening timing adjustments. Adjustments of the spark timing and the exhaust valve opening timing may change depending on whether a transient fuel shut off event of an auto-stop event occurs.

Abstract: Systems and methods for stopping and starting a direct injection engine are described. In one example, the air is injected into one or more pre-chambers of engine cylinders to adjust engine pumping torque during an engine stop so that the engine may stop at a crankshaft position that facilitates direct engine starting.

Abstract: Methods and systems are provided for transferring hot, compressed gases from one cylinder to another cylinder while fuel injection in both cylinders is deactivated. In one example, a method may include during a fuel shut-off event, opening a first pre-chamber injector of the first cylinder undergoing late compression or early expansion and opening a second pre-chamber injector of the second cylinder undergoing a late expansion and/or exhaust stroke or undergoing an intake stroke to allow a hot, compressed gas from the first cylinder to transfer to the second cylinder through the first and second pre-chamber injectors.

Abstract: Methods and systems are provided for controlling and monitoring intake and exhaust poppet valves of an internal combustion engine. In one example, the methods and system include feedback control that estimates intake and exhaust valve timing based on output of an in cylinder pressure sensor. In another example, the methods and system include compensation for feedforward control of intake and exhaust valves based on output of the in cylinder pressure sensor.

Abstract: A method for operating an engine during a fuel cut-off mode is disclosed. The method may adjust exhaust valve opening timing and exhaust valve lift of one or more cylinders to heat air flowing through the one or more cylinders so that a temperature of an after treatment device may be maintained or increased.

Abstract: Methods and systems are provided for reducing emissions during an engine cold start. In one example, a method may include, during emission control device heating, initiating combustion in a cylinder via a spark plug directly coupled to the cylinder and providing secondary air via a turbulent jet ignition system. In this way, an amount of hydrocarbons in feedgas provided to the emission control device prior to the emission control device reaching its light-off temperature may be reduced.

Abstract: Systems and methods for stopping and starting a direct injection engine are described. In one example, the air is injected into one or more pre-chambers of engine cylinders to adjust engine pumping torque during an engine stop so that the engine may stop at a crankshaft position that facilitates direct engine starting.

Abstract: Methods and systems are provided for improving turbocharger response in a boosted engine. In one example, a current turbocharger performance may be monitored, if meeting and operating in an optimum region for efficiency (e.g., on compressor and/or turbine maps), engine may be operated with a steady state exhaust valve opening (EVO) timing in an optimum position based on engine mapping (e.g., engine pumping work). Otherwise, the EVO timing may be advanced (opening earlier) to release more energy into the exhaust or retarded to release less, to move turbocharger to desired performance. By adjusting EVO timing to achieve desired turbocharger response and performance, faster response is achieved.

Abstract: Methods and systems for operating an engine that is coupled to a transmission that includes a power take off output are presented. In one non-limiting example, the engine may be operated in a speed control mode and a user may request smoother engine operation or more efficient engine operation via a human/machine interface. The more efficient engine operation may include operating the engine with fewer activated cylinders as compared to operating the engine for smoother engine operation.

Abstract: Systems and methods for stopping and starting a direct injection engine are described. In one example, the air is injected into one or more pre-chambers of engine cylinders to adjust engine pumping torque during an engine stop so that the engine may stop at a crankshaft position that facilitates direct engine starting.

Abstract: Methods and systems for adjusting engine knock control system dynamic gains are presented. In one example, a plurality of tables or functions output gain values, each of which is adjusted via a unique weighting factor. A rectified and integrated engine knock sensor level is adjusted according to a sum of weighted gain output values of the plurality of tables or functions.