Ran out of gas - added gas to tank and it will not start. on 2000 Mercury Grand Marquis

Does it need to be primed or what? I poured a little gas into the throttle body and it started but then stalled again. Why would it not be getting fuel now? And how do I fix it?

I would try to add more fuel like dan said if this does not work i would try replacing the fuel pump relay if this doesn't work i would check the fuel pump, and get a diagnostic to see if they are any codes
1 more answer , 1 more comment
The low fuel level sensor may be stuck on the bottom of the tank. How much fuel did you put in. It should be at least 5 or more gallons.

the fuel level sensor can shut down the injection system on many cars, meaning it can shut down the fuel pump so you don't run the fuel pump dry which can ruin it. The fuel is what lubricates the pump.
If I'm doing the math right, it would be right at about 5 gallons added....guess I will try putting more in and see if that works. But even if the sensor is stuck, wouldn't the fuel pump suck it up?