So, I Have owned my 1985 300d turbo for about a month now. About 2 weeks ago the drivers side rear window would not roll down but then days later it did and seemed fine. Just yesterday, I opened my trunk and the horn started beeping like crazy. Once it stopped I went about my business until I had to open it again upon my return home. It started beeping again so I locked and unlocked the car which seemed to make it stop. Today I opened it again and there was the beeping. I went to try the locking/unlocking thing again and the passenger side front lock was slow to respond and the two back locks hardly responded. Is this an indication that my vacuum pump is going?