2000 Chevy Silverado Engine Dies, Then runs rough

My truck is intermittently cutting out. I was told by a repair shop that my crank shaft position sensor was bad so I replaced it. It ran great after replacement and then out of the blue it stumbled on the highway and died. Now it seemed like the longer I let it set the better it would try to start. But then it dies once I try to give it any gas. I sprayed starter fluid in during one of these episodes and the thing cranked right up for a fews seconds on that. So im thinking its the fuel pump but before I replace it is there any sensor that may be bad? Right now it starts great until I give it gas and it starts to stumble like it loses fuel. I checked the fuel pressure regulator and it has no gas in the line. It also runs the same way with the MAP sensor unplugged. I even replaced the fuses for the fuel pump. No check engine light either. I also replaced fuel filter.