Hello all, New to this forum but need help with my e270 w211 cdi 2003 110,000 mile avantgarde. Brilliant car, owned it for 6 months or so with no issues other than a big puff of black somke after steady driving if I have to kickdown, presumably injectors need a clean. also sbc is noisy but i'm told that's very common and OK. After a 120 mile trip today just as I was close to home, I noticed a tinny rattle from under the bonnet that became a whine coupled to engine revs. got home OK car still driving perfect. at first I thought it might have been air con pump as it's been a warm day and I have been running air con all day. left car two hours but noise still is there. sounds like a rattling plate under the bonnet but realy not sure. also noticed a puff of white smoke when I blipped the throttle, not noticed this before. worried it may be turbo related but could be something very simple such as belt tensioner etc. any ideas would be greatly appreciated as I am new to Mercedes diesels. love the car but worried now about some big repair bill... regards. Lee J.