Car not starting.

I have a 2001 Hyundai Accent 1.6l engine. It's
cranking but not starting. I have replaced the
crankshaft sensor, camshaft sensor, plugs, wires,
ignition coil, fuel pump, and fuel filter. I couldn't
hear the fuel pump engage. Still nothing. A friend
hooked up a computer and got a crankshaft sensor
error, so I got another one and put it in.
Disconnected the battery to reset the computer.
After hooking the battery back up and spraying
some starter fluid, I almost got it to start. I could
now hear the fuel pump engage and after turning
the ignition on and off 3 or 4 times to build fuel
pressure, and trying to start the car I am back to no
sound from the fuel pump. What could be causing
the crankshaft sensor and fuel pump to not work? I
am at a complete loss.