While driving any speed after a few min it cuts out and spudders and looses speed put in neutral turn it off and crack it back up it runs fine for a few minutes , if given full throttle it does the same , followed another forum and replaced the fuel pressure regulator . No resolution . Truck still has egr and smog pump . Should I chase a fuel problem , previous owner says he replaced rear tank pump with in the last few months and front pump still needs replaced . Any suggestions will help thank you in advance!

 

If you replaced the fuel filter, what comes out of it can tell you a lot..
Get hold of a fuel pressure gauge and confirm fuel pressure is not dropping.
If all is well, then you might want to verify the 5 volt reference voltage is not dropping out.
Depending on what you find , we can go from there.

 

Connect a fuel pressure gauge so you can monitor it while driving. You should have 30-45 psi at all times if your fuel pump is working. Don't mess with the regulator unless it is leaking. It actually keeps the pressure from going too high.