for the past 2 days my transmission been giving me problems...x5 2002 4.4 auto, 111k, the problem im having is that the car would drive fine for about 20 mins after that if i come to a complete stop and press on the gas it would move very slow and sometime it wont move n then just jump, n there are other times i would try n to put it into drive and it will not say in drive (while in park getting ready to move, not while driving) it would go to neutral i notice that when the car is fully warmed up...CEL is also on...the code im getting is P0721 Output Speed Sensor Circuit Range/Performance...any idea?