Hi I have a 200 Tdi and its developed a noise around the bottom end of the engine I noticed when idling that the bottom crank pulley apears to wobble and is causing this noise. Can that be loose...I asked someone and they said it could be wear on the woodruff key or the crank shaft itself and could be terminal.. is this the case or have you heard of this before it still drives ok but does have slight vibration.....Regards Rog xx