Alex, My w201 has had the same issue. The dealer (done with those guys what a bunch of hacks) did me a favor of hacking up the plastic shroud around the motor and not snapping back in place the spring steel pieces that hold the shroud together. It is not that difficult to see if the plastic shroud is installed correctly. If you are going to the trouble, I would replace the motor. The one in my w201 is still factory with 203,600 miles, so I doubt the bearings are the issue.