the vacuum (system?) controlled door locks on my '81 240d haven't worked in a long time. i've never bothered to figure out if it was the pump, or just a leak, or whatever. i'm the only one who rides in the vehicle 99.9% of the time so i just unlock the drivers door with the key.

well tonight i was rolling down the road coming back from work and i heard this hissing noise which i didn't recognize over the radio. which of course caused emergency sirens to go off in my head, but upon turning down the radio i found that it seemed to be coming from the seam where the driver's side door attaches to the frame. i noticed i had somehow managed to set my elbow or something on the little ... um .... the knob to lock the door. so i pulled it up and the hissing stopped. locked it again, more hissing.

i know exactly jack about vacuum controlled door locks. is the evidence i discovered tonight indicitive of anything in particular, and if so what would be necessary to fix it?

thanks,

--Nick