Abstract: Systems and methods for operating a driveline of a hybrid vehicle are presented. In one example, torque capacity of a driveline disconnect is coordinated with torque control of an electric machine immediately following engine starting. The electric machine and the driveline disconnect clutch may assist starting of an engine, or alternatively, the engine may be started via a starter motor.

Abstract: Systems and methods for starting an internal combustion engine of a hybrid vehicle are presented. In one example, the internal combustion is started via closing a driveline disconnect clutch and limiting a torque output rate of an electric machine so that vehicle speed may increase continuously without decreasing during engine cranking and run-up periods.

Abstract: Methods and systems are provided for a drivetrain system comprising: a first prime mover for supplying a torque to a front axle; a second prime mover for supplying a torque to a rear axle; and a controller configured to, in response to a torque reversal, command the front axle and the rear axle to cross lash zones sequentially.

Abstract: Methods and systems are provided for reducing port injection fuel errors by selectively reactivating a direct fuel injector. Responsive to an increase in driver demand received while delivering fuel to a cylinder via port injection only, wherein the increase in driver demand is received late in the port injection window, the port injection error is addressed by reactivating a direct injector on the same engine cycle and delivering at least a portion of the fuel mass corresponding to the error via the direct injector. Additionally, a portion of the fuel mass may be delivered by the port injector on the same engine cycle by extending the end of injection timing, if possible.

Abstract: A vehicle includes a powertrain and a controller. The powertrain includes a powerplant. The controller is programmed to, responsive to a tip-in resulting in a powertrain torque direction reversal and upon obtaining a base value of a desired powertrain lash angle, adjust a powerplant torque schedule. The controller is then subsequently programmed to adjust the desired powertrain lash angle from the base to an adjusted value based on an observed powertrain lash angle that corresponds to a maximum powertrain acceleration during the tip-in.

Abstract: A vehicle includes a powertrain and a controller. The powertrain includes a powerplant. The controller is programmed to, responsive to a tip-in resulting in a powertrain torque direction reversal and upon obtaining a base value of a desired powertrain lash angle, adjust a powerplant torque schedule. The controller is then subsequently programmed to adjust the desired powertrain lash angle from the base to an adjusted value based on an observed powertrain lash angle that corresponds to a maximum powertrain acceleration during the tip-in.

Abstract: Methods and systems are provided for reducing port injection fuel errors by selectively reactivating a direct fuel injector. Responsive to an increase in driver demand received while delivering fuel to a cylinder via port injection only, wherein the increase in driver demand is received late in the port injection window, the port injection error is addressed by reactivating a direct injector on the same engine cycle and delivering at least a portion of the fuel mass corresponding to the error via the direct injector. Additionally, a portion of the fuel mass may be delivered by the port injector on the same engine cycle by extending the end of injection timing, if possible.

Abstract: Methods and systems are provided for reducing port injection fuel errors by selectively reactivating a direct fuel injector. Responsive to an increase in driver demand received while delivering fuel to a cylinder via port injection only, wherein the increase in driver demand is received late in the port injection window, the port injection error is addressed by reactivating a direct injector on the same engine cycle and delivering at least a portion of the fuel mass corresponding to the error via the direct injector. Additionally, a portion of the fuel mass may be delivered by the port injector on the same engine cycle by extending the end of injection timing, if possible.

Abstract: A system and method for controlling backlash in a vehicle powertrain includes the step of controlling a torque request of the powertrain with a first control strategy after an occurrence of a backlash predictor and prior to an occurrence of backlash. The first control strategy is modified when backlash occurs during the first control strategy. The torque request is controlled with the modified first control strategy after another occurrence of a backlash predictor and before another occurrence of backlash.

Abstract: Methods and systems are provided for reducing port injection fuel errors by selectively reactivating a direct fuel injector. Responsive to an increase in driver demand received while delivering fuel to a cylinder via port injection only, wherein the increase in driver demand is received late in the port injection window, the port injection error is addressed by reactivating a direct injector on the same engine cycle and delivering at least a portion of the fuel mass corresponding to the error via the direct injector. Additionally, a portion of the fuel mass may be delivered by the port injector on the same engine cycle by extending the end of injection timing, if possible.

Abstract: A system and method for controlling backlash in a vehicle powertrain includes the step of controlling a torque request of the powertrain with a first control strategy after an occurrence of a backlash predictor and before an occurrence of a backlash. Another step may be employed whereby the torque request is controlled with a second control strategy after the first control strategy and before the occurrence of the backlash such that a torque request level is below a highest torque request level obtained during the first control-strategy.

Abstract: Methods and systems are provided for reducing port injection fuel errors by selectively reactivating a direct fuel injector. Responsive to an increase in driver demand received while delivering fuel to a cylinder via port injection only, wherein the increase in driver demand is received late in the port injection window, the port injection error is addressed by reactivating a direct injector on the same engine cycle and delivering at least a portion of the fuel mass corresponding to the error via the direct injector. Additionally, a portion of the fuel mass may be delivered by the port injector on the same engine cycle by extending the end of injection timing, if possible.

Abstract: A system and method for controlling backlash in a vehicle powertrain includes the step of controlling a torque request of the powertrain with a first control strategy after an occurrence of a backlash predictor and before an occurrence of a backlash. Another step may be employed whereby the torque request is controlled with a second control strategy after the first control strategy and before the occurrence of the backlash such that a torque request level is below a highest torque request level obtained during the first control-strategy.

Abstract: A system and method for controlling backlash in a vehicle powertrain includes the step of controlling a torque request of the powertrain with a first control strategy after an occurrence of a backlash predictor and prior to an occurrence of backlash. The first control strategy is modified when backlash occurs during the first control strategy. The torque request is controlled with the modified first control strategy after another occurrence of a backlash predictor and before another occurrence of backlash.

Abstract: Methods and systems are provided for reducing port injection fuel errors by selectively reactivating a direct fuel injector. Responsive to an increase in driver demand received while delivering fuel to a cylinder via port injection only, wherein the increase in driver demand is received late in the port injection window, the port injection error is addressed by reactivating a direct injector on the same engine cycle and delivering at least a portion of the fuel mass corresponding to the error via the direct injector. Additionally, a portion of the fuel mass may be delivered by the port injector on the same engine cycle by extending the end of injection timing, if possible.

Abstract: A system for improving operation of an EGR system is presented. The system provides distinct models to estimate EGR temperature in response to a valve position. In one example, the system can judge EGR system operation when a state of a control valve is adjusted during driving conditions.

Abstract: A system for improving operation of an EGR system is presented. The system provides distinct models to estimate EGR temperature in response to a valve position. In one example, the system can judge EGR system operation when a state of a control valve is adjusted during driving conditions.