2) When cold, the drivers door is very difficult to unlock. Sometimes I have to open the lock of the passenger side, and then all locks are accessible. Is lubricating the lock with graphit powder the solution? I have tried a special fluid but it didn't really worked.
If someone used the wrong lube it could be gummed up. I would try flushing it out with brake cleaner or carb cleaner. Work it with the key easily until it turns easily, let it dry a day and then use graphite.
3) This pipe seems to be connected from the exhaust header on the brake servo unit. As far as I know, the brake servo requires the manifold (under-)pressure to operate? So what is the purpose of this line?
That is connected to the intake manifold. The exhaust is on the other side of the engine.
95 E34 530I V2.37
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