there a couple of threads on this subject. One I started due to a surging problem in my TD and Can-do started a poll on this subject. I ony have the problem when the engine is cold. I haven't really driven my '80 SD to notice if it's doing the same thing. IF it is then there has to be something going on, because my SD went through last winter without any problems. I wish I could pass along some tips, but I am still trying to figure this one out myself.
BTW it does seem the "SD"s drive much faster than the D and TDs. My SD accelerates like a gas car, with very similar throttle response. My neighbor also owns an '80 SD and his is the same way. However, my TD accelerates like my father's '85 300D, you have to really lean into the pedal to get them going and to get the turbo to spool up. It just seems strange, the differences between the SDs and the Ds when they both have the same engine. The only real difference I can see is the EGR valve on the W123s.

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member