I have had an intermittant rough idle for a couple of years and just recently started to have a problem starting the car (long cranking time) after it sat for a few days. If I turn the key on but did not start it for 20-30 seconds it would start right away. In searching the archives I found the answer for the hard starting to be the Fuel Pump Checkvalves. I replaced them and the hard starting is gone but to my suprise so is the rough idle. Another easy and inexpensive fix do to the information here on the shop forum. Thanks to all who share their experiences and especially to
Steve B. and MBDoc for all of their time spent helping and explaining to those of us that do not work on MB cars for a living. If it weren't for this forum I would not have purchased a second MB. PS. Fastlane is fast and afordable.