1981 240d vac problems

[Glacierbut]

I have learned a great deal from all of you pros out there on this site. I have a 1981 240D with an automatic tranny. Have been getting this ol diva fixed up best I can. One issue I am having problems with(of course) is vacuum. The car only has 128,000 miles on her. there must be a leak in the vacuum system as the tranny does not always shift when it should. When I plugged the two vacuum lines leading to all of the locking system, she shifted like a bat out of hell. Very smooth and crisp. Might even say the old car was fast and sporty. Stop laughing! She can hear you. The only problem was that the engine would not shut off. Once I re-attached the locking system vac lines, the engine finially shut off. The door locks work, they just take awhile to engage. There is some oil in the vac lines and at the key switch. Do I need to do a vac pump rebuild? I ordered some paper type filters to install in vac line to get out the oil. Not sure what the best approach is. I could live without the door locks if I keep the lines plugged, just need to be able to shut the car off.
I would appreciate any suggestions you might have.
Thanks

[tangofox007]

It sounds like you need to isolate the door locks downstream from the shut-off vacuum line. Leaking door lock actuators are a likely cause of your problem. You just need to isolate the door locks in a way that does not affect the shut-down vacuum supply (usually a brown line.)

[hockeynut]

Oh man, sounds all too familiar. If you have oil in the lines you have or did have a bad Vac shut off switch. Lots of threads on this. If it is shutting off OK, someone may have replaced it but never cleaned the lines out or it may be starting to go bad, but still provides enough vacuum to shut off the engine. You should take them off and clean with brake cleaner or equivilent. Should unplug and clean at the keyswitch as well. You don't want all that oil around in there. You can unplug at the valve by the ignition and run the cleaner from the other end of the lines in the engine compartment. Catch the runoff in something or you will have stained carpets. Ask me how I know this

As for the shifting, that is good news it shifts well when you isolate some lines, that means you don't have to mess with trying to adjust the Tranny at all. You need to figure out where your leak(s) is coming form. Many threads on this as well - good to have a vac gauge and a Mity Vac. Mine was from the line going to the HVAC control behind the dash - I just plugged that line off and plugged where it "T" off from, no more Vac leak. I didn't need that center diaphram to work anyway. Have fun