After running out of gas. It won't start.

Fuel pumps are lubricated by the fuel so running out of gas can burn out the pump. I would check that first.

Perhaps it didn't actually 'run out of gas' .. Listen at tank filler neck with cap removed for fuel pump to turn on when a helper turns key on .. IF pump CAN be heard .. TEST for ignition spark from coil and from spark plug wire(s) ........ IF in doubt about the fuel pump .. Fuel pressure is easily TESTED with a test gauge on the 4.3L .