Hi I have recently had a new turbo fitted on my 2.0l tdi 170bhp. Turbo seems to running fine but on pulling off there is quite bad turbo lag and black smoke out of exhaust. If I let my foot off the gas and re-apply turbo kicks in fine no smoke and pulls like a train. My original turbo seals went plooms of black smoke oil all over the back of my car! If anyone has any idea or had any similar problem I would be massively grateful of any advice or possible fix many thanks in advance.