I am new to FTE and also new to the 6.4L diesels. I just bought my 2009 F 350 two weeks ago. This has happened twice now since owning and I am not sure what to do. This truck has 151,000, DPF delete with single tune. Shortly after starting the truck it will lope like it is about to die and seems to be short of power and struggles to get going. I can stop and shut the truck off, restart, and all issues go away. All the power is back with a smooth idle. I drove the truck for a few days and experienced the problem this morning on the way to work. I don't see any warning lights coming on. I know that there can be a long of list of possibilities, but want to start ruling things out as fast as possible before any severe damage happens.

 

Scan for codes...sounds like a sticking EGR valve to me. You didn't say whether you deleted that.

 

Check for codes as Senix stated. Have you been running a diesel additive? I'm leaning towards an injector issue. "Contribution/cylinder imbalance."