i have a 91 s-10 thats been nothing but truble since i got it right now its idleing up and down then when i push on the gas it hesates then starts to go up in rpms and when driving it it bucks really bad when i push the gas its like it loses all power the slowly gains it

The 2 things that I would do is first check for any vacuum leaks. If the motor rev's up while spraying WD40 onto a vacuum conection you found a leak.

And if that doesn't work do a complete tune up.
Including change the fuel filter.
If you haven't changed your fuel filter in a while change it anyways.
The best way to burn out your very expensive fuel pump is by letting the fuel filter get plugged

i have changed the fuel filter along with the tps,fuel injector,igintion mod,cap and roter,memcals comp, and still nothing it runs the same

oh and ive changed the fuel pump

Oh, Welcome to the forum! I hope that you check in from time to time.

It's nice to see someone that does a tune up when it might help.

It still sounds like a vacuum leak to me, so that is where I would start.

I didn't really think that a tune up would help, which is why I didn't write it down first.
But it does solve most problems that people have

ive all ready checked for vacum leaks

when i did a self diagnostic it came up with tps low voltage but then i removed the ground cable from the battery and ran the truck for 20-30 mins then did the diagonstic agin but nothing came up