Thanks all for the help.

No, the rough idle is not just at startup. It's when I stop at a light, etc. Sometimes it's there, sometimes it's not. Most of the time it is.

I have been put in touch with a local mechanic that does only Benzes and he comes highly recommended. Think I will take the car to him and say "Check the timing chain, do the valve adjustment, check glow plugs, and clean the injectors". Ideally, I hope one day to do all this myself, but it might be a good idea to have a pro check things out the first time.

Thanks