Bad fuel pump?

[1993ranger_ohv]

Ok so i have a 1993 4.0 ford ranger. I use it mainly for off road. The other day i took her out for a spin, pulled into my driveway and park it. Got back in it and it would not start. So i took the fuel line off going to the filter and i was getting fuel there. So i sprayed starting fluid into the intak and it started right up ideled fine so i drove it a few miles ran fine, but when i cut it off it would do the same thing. Only start with starting fluid. Anyone have anyclue what could cause this?

 

[Dirtman]

Loosing pressure somewhere, check the vacuum hose on the fuel pressure regulator but more than likely the fuel pump relief valve.