Just found and fixed a vac leak in my 240D using this thread,
Vacuum help?
and in particular, the advice from dmorrison (thanks Dave!). I just started at the fire wall and kept working my way back. Make sure that you look at all the junctions logically (you will find them under the carpet, under the black plastic protective channels) and use your golf tee to isolate components properly as you test them. Search, read, and then dive in. Things will become clearer as you go. I can’t imagine you can do the job without some type of mity-vac tester. I borrowed one from our plant engineer at work.
I got lucky twice. 1st, I found the problem early in the trail at the lock actuator on the passenger door. 2nd, I went to my indy to get him to order the part for me, he rummaged around in a box, and handed me one, NO CHARGE!!!
Bonus feature! You get to learn how to take the door panel off. Look in the sticky's at the top of the forum for link's to the online manual with pictures at
"skinnerbox" to learn how to do this. It's easy, once you know how.
Clay