hope this will help someone.. Was having a problem with my 230sl . could not get it to run well sometimes it was super sometimes not so..in fact it was awful .. checked all the usual suspects with great assistance from the forum. I have not had the car for long so the history was lost. Was feeling helpless but persisted and finally after triple checking everything and I mean everything I checked the ground wire at the mounting point of the alternator and cleaned and tightened it and what do you know... success . Am not much for chatting on the web and maybe I should try and add more as This project will be with me for many years..Thanks for all the info , could not have done it without you