Sorry ahead time for the long post. I have a 2006 6.0L. Truck was leaking oil really bad. Took it to a shop and they said that the valve cover gaskets where leaking. I didn't have the time to replace the gaskets myself so I told the shop to go ahead and fix the oil leak. I go to check on the truck and the engine sitting on the floor, the shop was fixing all the oil leaks. They install the engine. I call 2 weeks later to see if they have it done yet and they tell me they are working on it that the truck has no boost pressure, no power and wont run over 35 with foot to the floor. After another week the truck still has the same problem. I go to pick it up and the shop says it needs a turbo, that they did take it apart and cleaned it. I get the truck back and I go back over what they have done, all the cac boot have been replaced, with new clamps. The clamps are so tight that the washer are split. I replace all the clamps myself. Found the y pipe to have a crack and the metal gasket torn. I replace the y pipe with an upgrade pipe and gasket, check for leaks (none) Found a hole in the line for the maf sensor. Cut the bad part of the hose off, blew through it making sure it's not plugged. Removed the EBP sensor cleaned the line, and sensor (it was pretty dirty) installed it. Check all the cac boot, no leaks. Had a code P0299 cleared it and it hasn't come back on. The truck will start and run. At idle I can here the engine sound change. I removed the air filter and can see the turbo spinning, when replacing the y pipe I check the play on the turbo shaft and it was good and would spin freely. I can drive the truck, no boost pressure on the gauge and with the pedal to the floor the truck wont go over 35mph. Starting to wonder if I have a fuel pressure issue and if it can somehow be tied to not having any boost pressure. Forgot to add that the truck doesn't have the egr cooler and the exhaust is straight piped. Any help would be great!