I have a 2011 ram 1500 with the 4.7 with 202,633 miles on it. I have been having problems starting my truck... At first it would turn over but not start, turn key off then restart and would start right up.... But got progressively worse.
It also felt like it had a lack of power. I replaced the crankshaft positioning sensor and The M.A.P. sensor which helped the sluggish feeling runs great..... BUT still have the starting issue if it sits for 3 hrs or overnight. If it sits over night I turn my key on ( But not start ) for 5 seconds then back off... back on for 5 seconds then start but won't fire. I have pushed the zert fitting on the fuel rail no fuel or pressure. I have given it a shot of starting fluid, It will start but stop when the first shot burns off... gave it a second shot started up and will keep running, actually runs great I've driven it around quite a bit. Good pickup no hesitation runs smooth. If I turn it off and try to restart it within 1/2 hour it starts. I replaced the fuel pump about 5 years ago although it was acting like it was not getting fuel it was actually the TIPM cracked underneath right at the fuse for the fuel pump. However it was not acting the way it is now. From what I can see it's losing fuel from the fuel rail. Is there a back flow valve that could have gone bad to leak the fuel back to tank ? I have looked and not found any leaks.

Thanks Jeff

 

I suspect the valve is part of the fuel pump module... what brand did you install when it died last time? Do you hear the pump run when you turn the key on?

 

+1
sounds like a fuel pressure leakdown issue. the leakdown can be either the check valve in the tanks as stated, or the injectors. I have been caught on this before..testing using a fuel gauge and shut off valve to block the supply line. If you really want to be sure...pull the rail with the injectors out of the manifold ( don't remove the injectors from the rail). prime the rail and put cups under each injector. If after 3 hours you have no drips/wet spots on the injectors...go fp module.

 

Thank you Hey you and premem, I replaced the pump using mopar pump from dodge dealer. - I haven't had the chance to listen for the pump to come on when I turn the Key ( waiting on my son lol ) but I don't hear it from the cab.
Once it starts it runs fine.
I wonder if I put a shut off valve on the fuel line under cab, to test it. turn it off to see if it leaks down.
Thanks
Jeff

 

Well seems I have a new problem I replaced the fuel pump, truck starts with no problem....... However when I connected the negative cable back on the battery the pump is running ??? this is with the key out of the ignition.
My battery went dead for no apparent reason last week ( thought maybe my son left the door ajar ) I now suspect that was the beginning of my fuel problems, thinking my old fuel pump was always running and got so weak it couldn't pump the fuel up to the fuel rail.
Is there a relay that would cause the fuel pump to run with the key out of the ignition ? of ignition switch bad ?
Thanks
Jeff

 

Fuel pump relay. Should be in the tipm under the hood.