Abstract: A system for controlling the engagement and disengagement of one or more clutches that are adapted to operatively connect an engine and an automatic transmission. The system including a control device for determining if a negative torque condition exists and to provide an output or signal to decrease the rotational speed of said engine in response to the determination of the existence of a negative torque condition.

Abstract: Prior to transitioning a multiple-displacement engine from a full-displacement engine operating mode to a partial-displacement engine operating mode, a base slip rate of a torque converter coupled to the engine engine is increased by a predetermined slip rate offset. The engine is then transitioned to partial-displacement mode upon the earlier of either achieving the desired offset slip rate, or once a maximum time delay has occurred since the slip rate offset was enabled. An offset slip rate is maintained throughout partial-displacement engine operation, and through a transition back to a full-displacement mode. The slip rate offset is removed or disenabled once the engine is again operating in the full-displacement mode. The slip rate offset is either a calibratable constant or is determined as a function of one or more suitable engine or vehicle operating parameters affecting vehicle NVH levels, such as engine speed and vehicle speed.

Abstract: A gear ratio selection method for a transmission in a motor vehicle includes detecting a power request, detecting a vehicle speed of the motor vehicle, and providing an engine speed of the motor vehicle. A first desired engine speed is calculated from a first variogram using the power request and the vehicle speed. A second desired engine speed is calculated from a second variogram using the power request and the vehicle speed. A blend factor is determined from the power request, the vehicle speed, and the engine speed. Finally, a blended desired engine speed is calculated from the first desired engine speed, the second desired engine speed, and the blend factor. The blended desired engine speed is used to determine a gear ratio for the continuously variable transmission.

Abstract: An electronic throttle controller adjusts vehicle acceleration based on accelerator pedal movement. The controller compares a rate of change of a pedal voltage with a rate of change of a filtered pedal voltage. The filtered pedal voltage depends on filter alpha values that vary as a function of engine speed divided by vehicle speed. If the rate of change of the pedal voltage exceeds the rate of change of the filtered pedal voltage by a threshold, the controller selects a performance mode. The performance mode determines how the controller adjusts a transmission ratio and power request damping. Additionally, the controller adjusts a duration of the performance mode based on an acceleration condition. The acceleration condition is indicative of whether engine speed, vehicle speed, and pedal position are constant.