I have a 2001 Audi A6 2.5 TDI 150HP (110KW) , and recently I have an annoying problem - when standing still in park or on "N" and reving between 1800 and 2500 rpm , the car shakes , as if it would be a petrol engine running without a spark plug ( although it s a diesel ). Everyting else is ok, no check engine light or any other errors showing up, and also when driving the car there is no shaking or rattle whatsoever. Above 3000 rpm , the shake stops completely and below 1500 it diminishes considerably, but there still is a light shake. When idling at normal 850 ( or 800 - don`t know exactly what rpm is at idling) there is no shake at all, but as soon as I touch the accelerator , i feel a slight shake . Anybody else had this problem ? Dealer says they might have to open the engine , and I don`t quite agree. Car has 220.000 km now, but I don`t think this is the problem , as it has been very well taken care of, from the start. Any help would be apreciated.