Found this disconnected by the battery. What is this and where does it go? Could it be the reason why the car won't start?
I've replaced the fuel filter and fuel pump relay....just checking anything else I can before I decide to replace the fuel pump...car cranks but won't fire....it'll fire with starting fluid.

 

If it fires on ether then u have a fuel problem someone definitely added or repaired wiring there though i would pull the cap off the shrader valve and see if fuel sprays out if so then u know pump is good do you hear fuel pump when u turn key on

 

I can't hear the fuel pump kick on. Fuel doesn't squirt out of the schrader valve. I've tried pressing it down while someone cranked the car over and nothing....no fuel came out of the valve.

 

That definitely is add-on stuff and probably not related to your problem. However, I would attempt to trace it and determine what those connections are used for.

Is there any aftermarket electronics on your car? Any evidence of hacked wiring?

You can temporarily by-pass the factory fuel pump circuit in order to test/run the fuel pump.