I am driving a 1994 C180 and it has several small problems I am annoyed at. First its the rearheadrest which is stuck and this is related to the buzzing noise in the rear boot which is the vacuum unit, secondly, its the centre airflow roller which is jammed, thirdly and the newest bug is that the speedometer hand or indicator is becoming stuck at zero for about 100 meters accelerating from 0 kph from redlights or from standing starts. Then it virtually springs up and jumps over the actual speed and settles correctly on where it should have been for the rest of the journey as long as I do not come to a standstill as it will start all over again. What is this??? Does it always have to happen to a Benz after a few years when everything starts to fail and stop working?? Never had this sort of thing happen to other car makes I have owned and driven , 2 Hondas, 1 Mitsubishi, 1 Mazda, 1 Fiat, 2 Toyotas. Can it be fixed easily and cheaply?