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

 

Vacuum system doesn't BLOW the oil in the lines. It SUCKS. So no need for filters.
Those transmissions are famous for irregular shifting, so that might have noting to do with vacuum at all.
Most common vacuum leak is the small diaphragm on the door mechanism. Lines go under the floor mat, so disconnecting them and plugging will pinpoint bad mechanism. Other way is watch them closing. The slowest one is usually the leaky.
Good luck.

 

Our 84 300 TDI was just in the shop for a month!!! waiting to figure out why she wouldn't shut off. Tried rebuild kit, $500, (I should mention that she's never shifted smoothly but when the locks wouldn't work and the engine wouldn't shut off all of a sudden on the ride home from work, text book for vacuum pump, we knew something blew or wouldn't blow!) fixed the locking system but not the shut off, tried new diaphragm, tried some new hoses, and finally on the 3rd week got the new vacuum pump, total of $1700 by this time. This is the only thing that would fix our shut off. Now she's back to her old self, I hope this saves you some trouble and money!