Thanks for reposting. I am going to have mine checked out. What bugs me most is that I have been to four diffent mechanics (including three Mercedes Dealers) and none have fixed the problem, and none have seemed to care about it in the least. One dealer noticed the rough idle when I was in for something else and had me book an appointment two weeks later. I took the car back and they told me there was no rough idle. Another Benz dealer told me to either pay 5 grand for a valve job or junk the car, and the third just didn't seem to care. "Live with it," they said. Hopefully my fix will be a nice and easy as your's was. Thanks again.
1995 E420 - retired
1986 420SEL - retired