2003 Expedition stops running

I should add that there is s buzzer in the fuse box that goes off when you try to start it. I have not traced it down yet.

I am going to answer my own question in case someone else can use this information. It turned out to be the fuse box. The Ford fuse box has internal relays that cannot be replaced, when they go bad the car won't run or start and they buzz. It costs about $400 for a new box and it takes a minimum of 4 hours to do the job. You need to remove all the plastic trim around the fuse box and the glove box. Under the hood you need to remove the battery and the battery box so you can snake the new battery cable through. To remove the fuse box you need to remove the 11 or 12 mm nut on the edge of the box and unplug the 12 plugs that go to it. The plugs are all unique as far as I can tell and the front ones are also color coded so there is no danger of mixing them up when you re- install them. One plug on the front requires that you pull up on a slide lock to remove it. There is a finger loop to help you unlock it. Installation is the reverse. Good luck.

F_O_R, I am having similar trouble with my Ford Exp. as well. I have not got in to tackle it yet. But I know when I parked it, it was running perfectly. Now, when I try to start it, it cranks, but the 'low oil pressure" indicator comes on. But will not start. Someone suggested perhaps a bad pressure sensor. And that maybe the low pressure signal would shut down the fuel pump and prevent it from starting. I have not noticed a buzzing from the fuse box that I am aware of. How did you ultimately discover the fuse box issue? Did you have it scanned? Thanks