I have an appointment to visit Mercedes service a week from this Friday so I do not know what codes are stored in the computer. I was just wondering if others had similar experiences that might indicate a common problem.
Last weekend I told my wife the car was idling like a 4 cylinder (not as smooth as usual but not horrible either). Your suggestion that it could be a partially blocked EGR tube could be the problem. For whatever reason, this may trip the CE light when driving short distances of less than a mile.
Thanks for your comments!