Hello together About a month ago I bought my second car until then – an Audi 90 2.3E, 136hp, NG, Bj 89. To the problem: If it is cold, the hydro-punchs are clapping like crazy, but after about 1-2Km then stops. Should, as I have experienced so far, be normal and also not bad. Does not bother me especially now. Sometime after a few more kilometers the clapper starts again… a lot quieter, but with radio and heating at the lowest level deutli Is somehow also not dependent on gas/not gas or the speed – it is then for a time “there” and disappears again… comes then again… and always so on. Oil change has been made directly after the purchase, filters also, timing belts have been renewed. Before the oil change the noises were NOT there by the way, only afterwards. I first suspected the workshop there something wrong to have tipped in and then I am to a VW workshop, starting from he thought the oil was ok and the flap would not be unusual for the old box. The last oil change was probably long ago. Then a hydro-punch additive tipped in, I thought, you can try it… Did not bring anything yet (about 200Km later) yet. Now my question: harms the engine, if I drive with it for another 1-2 months without having to do anything? For me it is actually clear that I have the hydros replaced then, the engine is damaged. clattering while driving annoys… Greeting Pascal