i have the same problem and after foolishly thinking it was the turbo because the symtems are a tell tale sign the turbo as packed in, it isnt the turbo more lkley it is the scraper rings in the pistons, is it belowing smoke if you take the filer cap of is it chugging like a train if so it is the rings letting to much oil in the chambers, either a new engine or a cheap engineer will sort this out, gooooooooood luck
paul doherty, March 2008