I have a 1995 6.5l turbo diesel. Within. The last year I have replaced notched heads, glow plugs injectors lift pump push rods and injection pump etc. History... I bought the truck with what I thought was a blown head gasket.... ended up being a cracked head so I replaced both with new heads and while I was there I did the go and injectors and push rods. Truck ran like a top after that for 7 months or so. Then I developed a problem where the truck with drive great for maybe 10 miles then lose power and buck almost and hesitant? Pull over shut her off and then it starts back up runs great for 5 mins then repeats the issue. So I thought it was crankshaft sensor or something electrical so I changed the sensor well it was AutoZone kind so my truck didn't start put old one in. Put my brand new back up mod in and took it for a spin and I can get 20 miles out of it maybe more like 10 miles then it does it again where I pull over shut off restart runs great then does it again in 5 mins. Pull over and shut down restart and I get 2 mins drive time then issue again. So I did lift pump air filter fuel filter and nothing changed. So I did the injection. Pump and still same issue so I parked the truck and it's been sitting for 6 months. I hit a frustration poi t where I almost drove it off a cliff I was so pissed off with this issue. So if it sits for three hours I can make it to the same place on my test route and without fail it acts up at the same spot every time. If I jump in it right now after sitting this long it will act up at the same exact spot it always does!? It's crazy. I been thinking these last few months that it has to be a clogged fuel sock? I do. I did drive it without the fuel cap and I did get a tiny bit further then usual. When this all was happening I got missed off and went home and left my truck at the shop and something told me to go back 5 hours later and crack the gas cap and I did and it did give that sucking sound after staying there 5 hours. I came across a thread here about a 94 Chevy with the exact issue and really want to know if it ever got resolved because I am at my breaking point. I am very mechanically inclined but not with diesels!!! I do have a tech one scan tool but the Damn truck will not give up a code which is weird seeing as it feels like it skips almost and hesitates, that's what leads me to think it's fuel related because it won't give up a code. Fuel sock clogged would be absolutely awesome or if some one on here knows what causes this issues? First time I noticed it had a issue I was backed down a boat ramp and I heard my truck stutter and blow black smoke but then it went away then 2 weeks later this happened and I spent some money on parts and the only thing that changed is my truck starts up just as fast as a gas motor with the new injection pump!! Runs awesome too for the first 10 miles!!! No modes on truck all stock besides a 3inch leveling kit. Please someone help, take a guess even it may help me get to the problem

 

Does sound like a fuel starvation issue. Sounds like you have already changed all the filters. Have you changed the fuel cap? It might be something cheap to try. It may not be letting the tank vent, and creating a vacuum. I reread your post, and you did say you removed the fuel cap to test it, so that eliminated that possibility. Another possibility is a rubber fuel line collapsing.

 

Defantly sounds like a line collapsing. I had the same issue and the rubber line that came up in front of the injector pump was colapsing.
fuel line is cheep and if you get a hose splice and hook to your line at the ip and the t valve then pull from your filter housing you can replace them with out pulling the intake. Just take it slow pulling so the line dont get damaged.

 

I can't for some reason reply to my own post to say thank u for ur advice about my 6.5 issues. I think u maybe correct. I did have an issue with that line to my up and filter and meant to change it while I had it all apart and didn't. It leaked near the connection so I cut it back 're hooked it up but it is solid as a rock in places to the touch so it may have collapsed