As Tony has said, does it smoke more if left to idol for a while, this could indicate turbo or valve steam seals.
A compression test will show a lot, if it's low (do this one cylinder at a time)add 10ml of oil into a cylinder and test again, this will seal around the rings and show if it's rings or valve that's causing the loss of compression, yes it'll smoke when you do start it later, but it's doing that anyway.