Thanks for your response Chuck and to the rest of you on this thread. I logged onto this thread because I have a 380SL and because I recognized so many similar problems that others had (Dennis and bad idle problems). My Beast did all of the idle things that most of you mentioned except that when it reached temp. and the idle reduced it stalled, except if I feathered the gas peddle and kept it running at +1400 RPM, and then it heated. The BENZ diagnosis said I needed 1) idle speed control 2) idle control valve 3) warm up regulator 4) oxygen sensor 5) Buzz valve 6) coolant temp sensor. When I obtained these items from a used 380SEL (same year) I took them down to a local garage to have them installed (I am not as dexterous as I once was, clumsy!). The garage replaced the parts and then the darn thing wouldn't start, let alone run. So they put the original parts back in and still no start, no spark! Now the mechanic is using a volt meter to trace the "no spark" problem and comes up with a small (1 inch square, 5 prongs, $178 from Toronto) relay from behind the glove box, a fuel relay that is putting out 7 volts and it shouldn't (he says holding the electronic diagram he downloaded off of the NET). I'm thinking that if the darn thing worked when I drove it down to the shop then why isn't it working now? I concluded that this mechanic was apprenticing at my expense. I also resolved to bite the bullet and have knowledgeable technicians look at it next summer when I get home again. One thing that haunts me is that it just may be that thingamajig fuel relay because of some of the comments on this thread. I have a few days left in CR before I have to return to -38C (-36F) country and I'd sure kick myself if it was that simple and that mechanic was right. How's that for self doubt? I have just enough time to order and install the part and spend the rest of the winter wondering or satisfied . . .hhhmmm??
I 'replaced' #1,2, & 3 above to finally answer your question Chuck.