I think that you may have an auxiliary vacuum pump in your trunk. If you do, it would be next to your spare tire on the right side, encased in a rubber mold. I have seen the electrical connector for one of these rot and not make contact anymore. This, however, was on a '84 W126...yours might not have this aux. pump.
[Edited by Larry Delor on 12-30-2000 at 08:53 PM]
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