METHOD AND SYSTEM FOR OPERATING A VEHICLE POWERTRAIN

摘要

A system and method for operating a vehicle powertrain are described. In one example, a torque converter that has a variable K factor is adjusted to improve vehicle operation. The system and method may improve vehicle launch and vehicle operation at lower vehicle speeds.

主权项

1. A method for operating a vehicle powertrain, comprising:
adjusting a K factor of a torque converter in response to a difference between a desired vehicle creep speed and an actual vehicle creep speed and absent a driver input demand torque while a transmission is operated in first gear; and increasing engine speed and engine air flow in response to an engine temperature less than a threshold temperature.