'93 190e 2.6, 81k

Hello friends:

My infamous chugging problem has re-developed again, and I'm not sure what the culprit is this time!!

This happens when I have driven for awhile, turn off the engine, come back and re-start. Cold starts are always fine - engine picks up and has lots of power. When it's warm however, it kind of shakes and sometime comes close to dying out, but never does. Acceleration is sluggish for the first 5 minutes or so, then is fine. Valve stem seals were replaced last year and that seemed to help a lot, but now it's back again.

Any other suggestions?

Thanks friends!

Take care-
Michael.