A few days ago out of the blue my truck wouldn't start, couldn't hear the fuel pump prime and no fuel was getting to the rail. I deduced that the fuel pump died, and replaced it. I can hear the pump prime now but the truck still wont turn over. I primed it multiple times before the first attempt to start it. I've noticed that there is air coming out of the Schrader valve on the rail when the pump is priming. any guesses as to what it could be?

Vehicle info:
2007 Ram 2500 5.7L

 

It cranks but won't fire?? Are you getting spark?

 

Haven't tested for spark yet I will update when I do.

 

So It does have spark. Hooked a pressure gauge to the valve on the rail and couldn’t get a reading

 

Won't run without fuel.