Patent ID: 7896114

Claim:
A method for starting an engine in a vehicle having an electric machine, a first clutch disposed between the engine and the electric machine for selectively connecting the engine to the electric machine, and a second clutch disposed between the electric machine and vehicle drive wheels, the second clutch being selectively engagable for facilitating torque transfer between the electric machine and the vehicle drive wheels, the method comprising: requesting an engine start; operating the electric machine; facilitating slip in the second clutch, thereby at least partially isolating the vehicle drive wheels from engine torque disturbances; engaging the first clutch with a rapid fill to bring a pressure of the first clutch to a first level; reducing the pressure of the first clutch to a second level, the second level being defined by a first function; reducing the pressure of the first clutch to a third level; controlling the pressure of the first clutch in accordance with a pressure profile until there is at least substantially no slipping in the first clutch; and fueling the engine, thereby facilitating torque production by the engine.