7.3 powerstroke hard/no start rough idle
 

I have looked everywhere and can not find a fix for this. If something has already beem found I apologize and please refer me to the answer. At first my truck was hard to start when cold and had a rough idle, most times when it would start it would have a looping idle for approximately 20 seconds. If I would plug it in overnight it would start just fine. The warmer the block, the easier the start. My first thought was gkow plugs. New gpr, glow plugs, and harness ( valve cover gasket and inner wiring). No fix. New fuel pump, fuel filter, and clenned filter housing. No fix. Now the truck sometimes will turn over without starting now matter if its warm or cold.
I cant think of everything right now. Any help is appreciated