Accelerates slow to around 10mph to 15mph then car drives normal again. on 1991 Toyota Camry

I just put a fuel pump on it. When accelerating from a stop car will barely pull like it doesn't have overdrive, or like it's not getting enough gas, but after it gets up to like 10 to 15 mph the car drives normal. After it gets to about 15mph it will down shift when you floor it and accelerate like it's suppose to. I can't seem to figure out what's wrong with it.

Asked by for the 1991 Toyota Camry
Going with the #1 theory , does it respond any different if you shift manually from 1st ?
It don't make no difference at all.
2 more answers , 1 more comment
sounds like a bad transmission
I was hoping that wasn't the response i was going to get....It was driving fine when the fuel pump went out, it sat for like a month and when I put a new fuel pump in it that's how it was acting.
Oh god I hope not. Mines doing same thing. I'll follow this post and update my first dings