Okay, so here's a story, tell me what you think. Not long after I bought my truck, it developed a smoking problem. If I was going up a hill, or was under any kind of acceleration, it would smoke. Not just a little wisp, a fairly good amount. It got to the point where I could barely drive the truck because of the smoke. Turns out the soot trap was clogged, and the turbo was junk. Slapped a new TCI GM-4 from Heath on, cut out the trap, and called it a day. This fixed the smoking issue. Obviously, the truck is not a powerhouse, it was stock with the soot trap cut out, but it would move pretty well for what it was. Fast forward about a bit, and the injection pump goes out. Without warning, the truck shut off as I was sitting in a parking lot. I had already relocated the PMD to the bumper with a Grey stanadyne PMD. We did some tests, had power to the lift pump, fuel to the filter, fuel at the T valve, no fuel at the injectors. So it got a reman pump from Pensacola Fuel Injection. Not long after that was done, a pretty reliable guy I know who is a diesel mechanic and knows the 6.5 very well said that Pensacola doesn't necessarily "rebuild" the pump, but instead simply reseals it. The pump with a new PMD, Dtech, ran me $650 with the core. If you buy just the pump, its $450 or $500 in that area. ANYWAYS, since this new pump has gone in, the truck feels a little less peppy, and I think it might a fuel delivery issue. I made a turbomaster, which is set to 10psi. As some have pointed out, the fact that I used a random spring, instead of a tested one like Heath's, could attribute to the lack of power, but I am not sure. I can hold 10psi all day long, and 12 on a hill. One day, I decided to take all spring tension off and see if the truck would smoke. It barely smoked at all, making 3psi max (there was some spring tension). I have seen 6.5's black out the road when they run without boost, so why doesn't mine? I installed a '93 lift pump, Delphi HFP905, in hopes that I would get a little more volume, no dice. The truck puffs a little smoke on startup, and a little on heavy acceleration, but it clears up almost instantly. Could my "reman" injection pump not be pushing enough fuel? Could my injectors that are in my 60k mile engine (truck has 160k they might be original to the truck) be worn out? What would cause this? Truck is bone stock in terms of fueling.