One more good evening/morning, I had to have a little bit of service on my 9-5 aero. The oil, oil filter and the front brake blocks were changed. What else has to be done is change the drive belt and the rear shock absorber (are leaking). The mechanic has emptied a “cleaner” in the engine before the oil change. This means that the dirt (e.g. from the coke) should be tied to it. In oil change this dirt is then removed from the engine. According to the mechanic the engine was not muddy, or there were only few traces to recognize. So as far as the engine mud is concerned, I can sleep with a calm conscience now. However, there is probably still a problem that makes me now, although it is covered by my quality 1 guarantee. The engine makes quite funny noises, which one hears especially in the empty chain. According to the mechanic, the mechanic will still be able to get in contact with the control chain for the compensation shafts or the control chain. He means that the chain has cost itself.