Lost vacuum so doesn't not function on all the doors; also engine continues to run after switching off.

Where do I look for leaks or malfunctioning parts. All hoses under hood near engine are connected.

This has been discussed a lot.
Use the serach function and search for

Door locks
Shutoff valve.
Vacuum pump
Vacuum system
ignition shutoff.

Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

you could have lost the vac pump or you could just have a leak..

this is not easy but it can be done.... i would start with a simple golf T
and i would start disconnecting near the brake master cylinder... and see if
i could luck into it... disconnect plug a line and then turn off the engine and see if it goes off.... and if you hit the right system you will have isolated the leak....

odds are its a leak back through one of the doors or in the trunk...

What car? If you have a vacuum pump under the rear seat, plumbing under the hood is irrelevant.

Steve

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'91 MB 190E 2.3
'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7

It is a 300TD 1985 wagon Problem started by not shutting off engine immediately and progressed to no shut off then to whole of door lock system.
RHOC