The fuel pressure regulator is located on the fuel rail on the engine. However, that is not your problem. The first thing that I want you to check is the power at the inertia switch. On your car it is in the trunk, behind a trim panel on the left rear. First make sure that the button is down. If it isn't there is your problem. If the button is down, using a test light, check to make sure that you have power at the switch, when the key is cycled from off to run (it will only be on for a few seconds, so you will need someone to cycle the key for you) If the test light does not light up then you probably have a bad relay or a blown fuse. The fuse is easy to check, it is labeled Fuel Pump and is located in the engine compartment fuse and relay box. If the fuse is okay then you have a bad CCRM (Constant Control Relay Module) It is a box located in the passanger side fender well and it contains the relays for the fuel pump, engine computer, cooling fan and A/C compressor. I hope that it is not the problem, because it is not cheap and a pain in the butt to get to. I am placing my bets on the fuse.
Let me know.
Did you try to start the car after pressing the switch?
Change the fuel filter and make sure that there is fuel in the tank. If you can hear the pump running that means that it is working. That means that the CCRM is okay. (which is a good thing).
If all that pans out, then you may have a bad fuel pump. I am hoping that you put in a Ford pump? I have had problems with the aftermarket ones (Napa, etc) but it is running so lets try the filter before we head anywhere else.
Yeah, I understand the pricing difference. But when you have to change it a couple of times the price kinda falls to the side. Get that filter changed out and let me know.
If you can hear the fuel pump running, then the relay is okay.
Next step is to make sure that you have fuel in the tank. It would not be the first time that a low tank caused a pump to burn out. The pump because it is in the tank, uses the fuel as a coolant. A low fuel tank, means the pump gets hot and eventually fails.
If you want to double check the relay, use the test light procedure that I outlined in the first answer, at the inertia switch. But since you can hear the pump, then the relay should be okay. (if the relay wasn't working, then the pump would not get any power and would not run)
I just thought of something, I have had aftermarket pumps wired up wrong and the pump ends up running, but turning the wrong way.