Our eagle eye well trained Mercedes specialist immediately spotted the problem.A new pair of Absorber Link is ready for the replacement.Diagnostic test on the old car battery yields poor results. The Test-Results printout recommends battery replacement.The brand new VARTA battery bidding farewell to the depleted counterpart. The Mercedes Benz E200 is returned to Mr. Joseph with no more knocking sound and our complimentary premium carwash and interior vacuuming.