The fuel pump does indeed have a check valve and it should hold pressure over night.Before you start it in the morning turn the key to the on position and leave it there for 15 seconds.Do this a couple of times before you start it.That should turn the fuel pump on and pressurize the system. If it starts right up you have a fuel pressure problem.If that is the case there are two things it can be. The fuel pump or a leaky injector.My money is on the fuel pump.You used to be able to jump the fuel pump from the diagnostic box(drivers side next to intake) by jumping Fp and B+ but I looked in mine and there is no conector in the Fp slot.