A method is presented for correcting estimates of engine output torque and
accessory load torque. Engine output torque estimates are corrected when
the accessory is disengaged from the engine. Accessory load torque is
learned, or corrected, when the accessory is engaged to the engine. In one
example, these corrections are made when engine output torque is known to
be substantially zero from torque converter speed ratio or from the timing
of the overrunning clutch engagement. This information is then used to
control engine output torque to improve drive feel and vehicle
performance.