I have seen them run with 40 psi, but would not start without being primed and did not have full power, but it saved the tow bill for the few blocks it was away from a place to work on it. Not reccommended, but it is possible. When you check the pressure you need the number the gauge is at when the pump is running. As stated, the pump will run for a couple of seconds to prime when the key is first turned on. There is a check valve in the pump which holds pressure, but it will drop a few lbs from full after the pump shuts down. It should then hold pressure for a while. Also, when was the last time the fuel filter was replaced? This can affect fuel pressure. If the fuel filter was not checked/changed regularly it can lead to fuel pump failure. If it were me, I would change the filter if it has been a while and check the pressure again. It may even be all that is wrong, as pressure and volume are two totally different thing. Again, try the filter first and see if that helps. It only takes 15 mins or so and is about $5. And it sure couldn't hurt.