Method for operating a vehicle having a disconnect clutch

A vehicle system, comprising:

• a driveline including an engine and an electric machine;
• a driveline disconnect clutch positioned in the driveline between the engine and the electric machine;
• and
• a controller including executable instructions stored in non-transitory memory to adjust a pressure applied to the driveline disconnect clutch as a function of a difference between an engine pull-up torque and a driver demand torque when the pressure applied to the driveline disconnect clutch is between a first pressure and a second pressure.

A vehicle operating method, comprising:

• adjusting a driveline disconnect clutch pressure to a torque stroke pressure via a controller in response to an engine pull-up torque minus a driver demand torque being less than a threshold;
• adjusting the driveline disconnect clutch pressure from the torque stroke pressure as a function of driver demand torque via the controller in response to the engine pull-up torque minus the driver demand torque being less than the threshold and in response to driver demand torque being less than the engine pull-up torque;
• and
• adjusting the driveline disconnect clutch pressure from a first pressure to a second pressure and starting an engine via a controller in response to the engine pull-up torque minus a driver demand torque being greater than the threshold and in response to an urgent engine start request.