a lot of people mistake burning oil for "white smoke" while those in the know call it "blue smoke." even though it looks white, it's more of a fogy white with a very subtle blue tint, where as burning coolant will look like steam, very transparent. first decide if it's burning oil, or water. oil can be leaking past your valve seals because of worn guides, or past your piston rings, or from blowby at high rpm forcing past your rings and through a fog of oil then through your PCV valve into your intake. pull that valve out and have a look at it. if it's soaked with oil, that's likely your problem. but if the valve appears to be burned looking, like some oil was on there, then baked on, then you can look to other sources.