Car bogs down when punched.

My 1994 corsica 3.1 drives very nicely. Idles slightly high but purring other wise. Revs up really fine. And when I go out and drive it it acts just fine until I want to hurry up. When I floor it it actually slows down, jerky like. There has been a lot of sensors replaced but all with used ones. It should be downshifting when I do it while driving but doesn't. And starting out from stop if I punch it the car will go a little then not.
Anyone have any ideas?

what sensors have you replaced?