First - replace the fuel filter. Tip: use the two-finger fuel-line plastic type where you can pull with your forefinger and index finger; the single-finger kind rarely works. Personally I use the metal scissors style. Even if you have a weak fuel pump, replacing the filter may help.
Second - listen for the fuel pump. It will spin up for about two seconds after you turn on the ignition.and then stop, I can usually hear it inside with windows closed; otherwise pull off the gas cap and have someone turn the key to ignition, but not all the way to start.
Third - I don't know if the Gen 3 (2001 and up) and up have an access plate. My three Gen 2 ('96, '96, and '00) I had to pull off skid pan and lower fuel tank, and then pull off left rear tire off to get to the fuel pump. I'm going to cut out an access panel on my '00, the pump is even with the front edge of left inside wheel wheel and about two inches to the center.
The entire pump assy (metal frame, float, and variable resistor) from Ford is over $500 at O'Reillys. The pump motor only about $100, and the kit with filter boot about $120. My resistor was tarnished and a light rub with an easier burnished up. I'm guessing at the prices as I have a commercial account and my price is usually half the street price.
few days ago i go to get in my 99 explr, and it wouldnt start, wouldnt even take a jump start, i go through all the checks, and nothing, no hidden codes, for some reason i check the air filter, and it seemed clean, then i banged on the bumper to clear some dust, some did come out but not much, anf after i put back in , it went and started up, and ran fine for two days, until this morning it did it again, 
, so of course first thing was to check for another dusty filter,and of course nothing 
