I have an SLK 350 with 1000 miles. When I start my car in the morning, the engine makes a ticking noise like a loud mechanical watch. The noise goes away after several minutes. I don't know a lot of technical details about cars, but I think it may sound like the ticking made by valve lifters in the old days (I don't know if cars today even have valve lifters). I took the car in for service two days ago and mentioned it to the dealer. The following morning they heard the noise too, but it went away before they could track it down. They plan to keep the car for another day or so to let it get cold, start it up and try to find the source. Has anyone else run into this issue?