'85 380se rough idle

[barndoor]

my 1985 380se has a rough idle,as if it is "missing"but when I give it gas,it doesn't miss at all.So I dont think it is missing?(spark) Could it be dirty injectors?I have searched this site for an answer,but haven't found one.This seems to be common to this car?or all 126's?.I pulled the "OVP" and re-inserted it.the car sometimes starts right up instantly,other times it takes a few seconds(a little too long)and then seems to smoke (black)on startup.If and when it instantly fires,it doesn't smoke at startup.I replaced the plugs,which had a little more carbon on them than I would like(running rich)I also replaced the cap and rotor.I just recently bought this car and am absolutly in love with it!But I cant stand the car "Rocking" at a stop light!
please help my Benz idle as it should.
thanks!!!,
Mark

'85 380se
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