I have a 96 e320 with 125,000miles. The car runs and idles good. Here are my problems, the power door locks don't work, the floor heat vents don't open, and I have a check engine p1700 code(a control emissions related on the transmission). I beleive they are all vacuum related,but maybe not the same source. I checked the motor on the vacuum pump under the back seat and it runs, but the pump does nothing when installed in the car. I don't have a guide to the fuses under the back seat, but they all appear to be good. Maybe the previous owner removed the fuse and never replaced it? There are four electrical connections to the pump, is there anything more I can check?