Where is the fuel pump relay, and how do I check for properly working?

It sounds like the engine oil pressure switch is not working or the engine is out of oil or has no oil pressure, I would bypass the sensor electrical connector with a jumper wire to see if the fuel pump comes on. Here is the location of the sensor which is in front of the starter motor and the wiring diagram so you can see how the system works. Check out the images (below). Please let us know what happens.