Fuel pressure and accelerating issue

I replaced a transmission, filter and neutral safety switch. It runs and shifts well. When I start it up, it will turn but it looks like there is no gas going in. So I have to put in starter fluid in. That is when it starts up pretty good. Most of the time I have to keep on doing that.
Also, I have another problem. When I push on the gas pedal it seems to lose power. Does not matter if I am going up hill or not. Before it takes off right away. Sometimes it pops underneath the hood.
What is the problem?