I recently bought a 2004 F-250 Lariat with an 05 engine. It runs perfectly when warm although its lacking power. From a cold start it sputters for about 2 minutes and then runs just fine. I think I have some sort of turbo leak from between the cab and the engine but I'm not sure from where... any ideas?

 

Your are most likely exactly right. There is the up pipes on the back of the engine. The rot out and leak where the corrugated meets the solid part. Happens all the time. And also will cause the exaCT same problems you are having. Kinda hard to see but take a look at the firewall of your truck. May be easier to see from the bottom looking up. Sometimes you can see from the top with an inspection mirror. But if it's black with soot then ththat is definetly your problem. No power at all runs very rough cold no boost til late in the rpms and won't get out of the way. Until it's warm. The gap closes up and your truck runs fine. Well still has some lag bc it's still slightly leaking. Sounds to me like you need a set of up pipes there my friend

 

that's close to what I thought... are up pipes different than Y pipes?

 

this is a completely different subject but when I bought the truck the A/C only blew through the defrost. I changed the vacuum pump and now it works fine unless I put it on max a/c... on max a/c it only blows through the defrost... I'm

 

Sounds like you have injector stiction as well either polish spool valves or order rev-x