Big shout out all you deisel fanatics im new to the deisel world 2 deisel truck my first ford but im having an issue i bought a 2004 ford f350 6.0 dually dont realy know much about the truck other than it was rebuilt engine about 80xxx miles ago well here i go every morning (cold)with out a dought this truck will start right up runs and drives great no problems shifts great idles perfect 70-80 down the freeway no issues the problem is when i turn it off it will not turn back on it cranks but will not turn on iv used starter fluid in the air filter and it will crank right up i know i know its bad for the deisel but i had no other option i have read about the ficm and how to check it and i did good 47v to 48v, tested batterys and they tested good disconnected and reconnected the ipc senser on passangers side valve cover cause thats what i had read up to try but it still does the same thing does any body have any idea what could be the cause of this or what to try to figure out the problem.

 

Welcome to the site

 

What do you mean "crank right up"? I fires and runs? Sounds like a glow plug issue

 

Most likely a High Pressure Oil leak, these trucks have 2 oil pumps, a low pressure/75psi for the engine and a High pressure/4000psi for the injectors. when you develop a leak, in your case a Late 04 truck it is either the "stand pipes" the "dummy plugs" or the "orings" on top of the injectors and on rare occasions it can be a Oring that sits on top of the pump/branch tube connector and seals to the cast iron HPOP cover. there is a test you can do,youtube is helpful, called an air test, what ou are doing is pressurizing the oil rails with air and listening for a leak but you also have to power the IPR valve closed to do this test.
on the later trucks/05and up there is a Snap To Connect fitting that is a common culprit bu your truck won't have that fitting.

 

bob has you on the right track. +1