94 Cierra Cutlass (S?)

For some reason my Olds will start, but after driving for a 15-20 minutes, it floods out, and dies. I've changed the spark plugs to no avail, I think it may be the fuel pump (I'm a programmer, not a mechanic), but I'd like to see what others think. Just before it dies it starts to backfire, like there'strash in the line, and, after it dies, if I wait for about five minutes, it'll start back up and run fine for another 5-10 minutes before dying again. I would greatly appreciate any help.