W126 cold start problem
I recently purchased a 1980 380SE German Spec. Vehicle runs great once warmed up but is almost impossible to start when cold. Initially thought it probably needed a tune-up since it did run ragged when I picked it up. So, off to the local MB dealer for a tune-up. Ran 100% better whan I got it back. Next morning still had the hard start problem. If I hold the gas down all the way it will eventually catch and run rough then pick up but will not run under 2500 RPM until the temp gets up a bit. Idles a little high too, around 1500 RPM. Took it back to the dealer and naturally they parked it in their heated shop overnight and it started fine so they said no problem. They have so far been unable to figure out what the cause is, even though they can reproduce the problem by leaving it parked outside in the sub-freezing weather overnight then attempting to start it. I have searched the forum and don't see anything similiar to this problem. Any ideas would be appreciated.