fuel problems I think

I have a 97 oldsmobile acheiva that will not stay running. I first thought that it was my fuel pump so I changed it. I also changed all the censors related with fuel system. I even went so far as to changing the brain in the car thinking that it was that . it seems like the car is not getting a enough pressure to make the gas reach the fuel injectors. I changed the fuel injectors as well. So I'm at a lost as to what to do next.

this was a mistake I was trying to read the posting.