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Hy! i ve got c180 (2005)manual petrol- ihave this problem with my speedometer which is oscilating slightly between 800 to 900 rpm! -any help will be much appreciated! can it be because of an not changed tensioner and rollers from the mercedes chain transmission? the car has been tested with a professional mercedes tool but no fault code detected!

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I suspect that there is nothing wrong with the speedometer but what you are looking at is a tachometer (engine RPM counter). Oscilations in engine RPM's is normal and generally points to a tuning problem of the engine. It may be from incorrect chain tension as this would change valve timing as the chain flaps around and cause a change in ignition timing as well. IF it concerns you the readjust the chain tension to the correct setting.

Posted on Dec 25, 2013

  • Stelian Margarit
    Stelian Margarit Dec 25, 2013

    Thank you for the answer! correct adjusment will be done by mechanics soon and hooefully this will solve the problem!



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