92 300D 2.5 won't idle on cold start,low idle speed on cold start

[klipweld]

Is there some thing that raises idle speed upon cold start up? I bought a 92 300D 2.5, a wouldn't start craigslist special. Fresh fuel & both fuel filters,and new glow plugs later it starts and runs smooth, WHEN warmed up . Problem is upon start up it dosn't want to idle smooth, when warming up, it will shake and stumble ,and will die.( Idle seems too low ) When warmed up , it idles fine, and is pretty quiet. Warm idles at 750 RPM, is that about right? What should I look at next? I have done the above, and will do oil & trans. fluid & filter change,and I will check brakes. At 229,xxx miles I have read to check timing chain stretch, that is on list. What else would a person do to a new car to check it out? I anxious to get it road ready. It runs down the road great, it's a rocket ship compared to our 83 240D ! Thanks for any help!