It will run alright for about 2 minutes then start to stall out I'm thinking vacuum or fuel pressure regulator. Any suggestions would be awesome or pics of how your vaccum looks I tried looking at diagram but find it hard to follow so if anyone could post some close ups of there engine that would be awesome

 

Have you changed the fuel filter??

 

Yes fuel pump and fuel filter are both new.

 

So I tried to set the timing and the timing mark keeps moving in a full circle so I'm thinking the harmonic balancer is bad can move it back and forth by hand. Also we. I start up it turns over for a when before it fires in park it idles good buy when I put In drive it idles really rough and will barely go it takes me about 3 minutes to get up to 45 then something opens or turns on and it loses all power complete and I can only go about 20mph until I restart the truck. The check engine light doesn't come on. Parts replaced so far are fuel pump fuel filter and fuel pressure regulator and the egr vaccum modulator all to no avail any help would be immensely appreciated