NEED HELP FAST STARTING PROBLEMS!!

Hey guys this is my first post so Im a little new to this but I just now got into XJs and I love them but Im having a few problems!!!
Everything was going great I put on a rough country 6.5" susp lift got some steel wheels and some 33" Goodyear Duratracs.
However I did all these mods and I have not got to go riding yet at all!!!
My xj was idling hot so I put in a 180 thermo and a new radiator just for the heck of it and I got my boys to pull it out of the garage,well they went riding in it and ran it out of gas,after that it wouldnt start ever since.
I put a new fuel filter and fuel pump on it but it still will not start????
The fuel pump is getting power while the ignition is turning over however
when I quit turning the key and try to let it run the pump is not getting any power to it.I did hot wire the pump just to make sure it was good and even the old one and actually both are good....so what do I do now????
I am up to any and all suggestions that are not dumb or someone trying to be a smart@@@.


Thanks for all the help!!!

Gotta know the year/engine to help you.

If you have a 93 or older, you have a "ballast resistor" somewhere on the fenderwell, I think it is on the driver's side.

If that resistor is bad, you will have fuel pump power when the key is in the START position, but when you release the key, you won't have fuel pump power.

Along with the ballast resistor, the ignition switch itself is a possibility.

Give us the year and we'll go from there.

BTW, if that new radiator didn't help your idle temp, the #1 cause of temperature creep at idle is a bad fan clutch. The stat won't do much here and a 195 is best
for most stock 4.0 applications.