i'm still working on this problem for my c230k
it sounds like it wants to stall on start up....like you gott heavy cam in your c class....
If you haven't done you normal troubleshooting
Check and clean the MAF
Check your Fuel Pressure
etc etc
i'm going to try another fuel injector treatment...i'm gonna get seafoam another try...if not 44k or somthing harsher