Hey guys, got a 92 Dodge Shadow america. 3 speed auto, 2.2L.

Issue with it that I'm sure about because Idk transmissions as well as I know chassis and engines.
When at a stop on a hill, The transmission seems to slip or something. Step on the throttle, and rpms go up, up up, car barely creeps, then BAM slams into gear and moves like a bat out of hell. I realize it;s in gear the whole time, so could be it that throttle pressure isn't high enough to move the car immediately? Could the throttle pressure regulator (the little valve thing that responds to throttle input) be going? Maybe the cable is bad? The fluid is pink, and not burned. On flat land it moves just like it should. Doesn't shift hard. Moves quiet nicely.

Any ideas?