1990 Chevy Silverado sensor maybe

My 1990 chevy truck accelerates fine but runs kind of jurky at crusing speed, ive also notice the problem when idling slowly uphill the engine will roar and kind of lerch forward as if you where to let a cluch out and push it back a couple of times even though my truck is an automatic. I tested the tps and it check out fine with a meter. It dosnt fell like a trans problem but more like a sensor or fuel problem?