'86 420SEL Rough initial idle when Hot

[Randy]

Hi, my '86 has developed a different kind of rough idle problem. When starting cold, it starts instantly and idles perfectly. On a hot restart after driving, it will start quickly but shake for about 5 to 5 seconbds, then smooth out and no more problem.
It has 162000 miles, and I have owned it since December 2003 with few problems. I changed the timing chain several years ago; new plugs, injectors and seals; typical periodic maintenance such as oil changes, coolant, et al. What do you think?