Does anyone know the signs of a fuel pump on it's way out?

Yeah, your engine won't run! Are you experiencing any symptoms?

When I start the car it runs fine for a little while, then while at idel the rpm's will drop down about 150-250 for about one second then they suddenly jump up to about 1000. It keeps doing this and if I sit long enough it sometimes stalls.
Thanks in advance

A fuel pressure test should give you a clue on the pump. I'd be checking out the idle air control valve and it's circuit on that one.