91 Buick Park Avenue rough run up hill

[lrice2]

car runs rough up hills, shakes, like torque convertor

has 214k miles
just bought month ago, december 2003
runs great on level except around 50mph shakes some

is that worthwhile to replace torque convertor, or just do more major transmission work since it has so many miles????

[lrice2]

also, this car shows code 31 but AUTOZONE can't tell me what it means, has several possibilities....
including "Circuit Fault"