Exhaust smoke

Looking for some guidance. Trucks deleted and tuned. 191xxx miles. I bought it a month ago as is. It still had the egr in place, but unhooked. A week ago I installed delete plates as well as trans tuning. I've found a pretty impressive amount of sludge in the top end, that I've done my best to clean out. Today I had the intake horn out and the grid heater was almost completely blocked, so I cut that out and did my best to vacuum and clean out the intake shelf, as well as the intake horn. There is some oil in the piping. With that out of the way onto the issue. When I get on it, 3/4 or more throttle, it'll smoke white. It also continues to smoke, almost bellow, after I get off the throttle, then stops. I'm starting to think it's from the oil in the intake. I've checked the coolant, and there no oil on top, and checking the dipstick it doesn't appear to have any milkiness. Should I be worried it's the head gasket? Or do you think it's just oil in the system. Runs 190-200, depending if I'm hard on it or towing. If I'm babying/cruising, it stays right at 191. Thanks

Turbo going south?

I don't believe so. It fealt fairly tight. From the ccv vent that was still routed to the intake with a ccv filter that hadn't been changed in who knows how long

Was this carbon build up your talking about? You called it sludge. Is it wet? Does it use oil?

In the valve cover, it was wet. But on the outside. I really don't know if I would call it soot that had oil mixed with it, or just somehow oil from something not changed. As for in the intake it was hard. Had to break it off the grid heater with my screwdriver and vac right on it. I have since deleted the ccv reroute and it's venting to atmosphere with a filter