truck starts good then runs rough after a few seconds

[killa071]

the truck is a 94.5 and the other day it started running funny so i changed the fuel filter and it ran good for a couple days then it did it again and i parked it so it starts fine and runs good for about 2 seconds then starts missing i let it run for a little bit and it cleared up for a few seconds then went back to rough again im thinking weak fuel pump maybe any ideas what should the fuel pressure be if i check it truck has 140000 miles no mods with a stick

[White95f250]

I'm bringing this back. Just ran into this similar problem. I'm about to change the fuel filter. I drained the water/fuel separator then this started happening.

[killa071]

Valve cover gaskets is what mine was

[White95f250]

Awesome, i'm doing all the basics while it's apart. Gaskets, glow plugs, fuel lines, filter etc.