I have a Grand Marquis,2003, that ran 6 months ago and will not start now. I have a fresh battery in it and it turns over very fast. Could this be a sign of a broken timming belt? How can I check that the fuel pump is working? Last, if it is something electrical, were should I start looking? Thanks for the help, I am new to the 4.6L motors.

 

as far as i know, your car has a timing chain not a belt.... when you turn the key to on position, without cranking engine, can you hear a small humming sound from gas tank? i myself dont know much about the 4.6L since i prefer the 5.0L of the earlier models

 

I will check again for the pump, but I did not know it was in the tank.

 

Well no hum or sound , but I can not hear any sound from another one I have and it starts. I checked all fuses and relays, even the shut off in the trunk. I can not see how to unhook the fuel lines at the engine, don't want to cut into them. Any ideas as to how to unhook them and check for gas flow that way?

 

There should be a fuel pressure test port.. It will be on top of the engine on the intake manifold. It looks sort of like a tire valve and is part of the fuel rails that feed the injectors (I believe these are still chromed on 03) If you take the little plastic cap off and press down on the small peg in the center of the valves it should squirt fuel out of there.. (May need a small screwdiver or something like that to press it down) You could also take the gas cap off and listen in the fuel fill spout while someone turnes the key on to see if you can hear a hum in the tank..
Check your fuses and the fuel pump cut off in the trunk if you have no fuel...

 

could be a severely clogged fuel filter also... girlfriends 1989 Crown Vic started and ran fine one day and next morning it wouldnt start.