Hello folks. I have a 2009 C300 Sport with just over 1000 miles on it. The car shakes and does a rough idle for 20-30 seconds during warm up (especially in the morning). I brought it back to the dealer and tehy found nothing wrong with it. They kept it overnight and tried it with two other 2009 C300 and found the same rough idle. I also spoke with somebody at MBUSA but got the same answer (emission issues). Does anyone here having the same issue or is it really an issue? Well, just thought that this type of car should have a better design than my Nissan pick up truck which starts rough too in the morning... I would really appreciate it if someone can give me a some logical explanation or resolution to my situation. Thanks.