US Patent 7275518 Torque-based powertrain control for vehicles

A system and method for controlling a vehicle powertrain having an internal combustion engine include determining a difference between a desired engine torque and a current engine torque, adjusting the difference based on a stored torque offset corresponding to a current engine speed, and controlling the engine to produce a torque corresponding to the adjusted torque difference. The stored torque offset is adjusted when the engine is operating in a predetermined engine speed range based on a steady-state difference between the desired and current engine torque to reduce the steady-state difference to zero. The adjusted torque difference may be limited by a maximum-engine-torque-available parameter and a minimum-engine-torque-available parameter, which is based on an operating temperature, such as the engine coolant temperature. The system and method may also include controlling spark to rapidly reduce current engine torque to the adjusted torque difference value.