1991 190 E door locks anomaly

[flowdrip]

Some punks tried to break into my car while I was out of town by playing with the drivers side door and lock. Ever since then my key doesn't work in it. So I decided to get off my butt and fix it, got a new lock, installed it, then ran into this problem. The locks only work with the engine running. As soon as I shut off the engine, I lose all vaccuum. Isn't there some sort of vaccuum resevoir that would keep the system under vaccuum so you could lock and unlock the car with the engine off? Or do I just have a bad vaccuum leak? I tested the vaccuum lines one at a time and the only leak I found was the line that comes from the drivers side lock, right in front of the drivers seat, the line splits into 2, and one of them didn't hold the vaccuum. Problem is, I can't figure out where it was going to. It continued under the seat but didn't show up under the rear seat bench like I thought it would. Any suggestions would be greatly appreciated.