I localized a vacuum leak in my 84 300d somewhere in the drivers side door. When the door is locked, the auto transmission shifts hard and cant turn off the engine. Obvious solution, I dont lock my door when driving. However, how serious is this leak? Is it something that needs to be repaired immediatly, or can it wait till I figure how to do it myself?

The leak isn't necessarily in the driver's door. The lock on that door activates a valve that routes vacuum to all the other doors, plus the fuel filler and the trunk. So the leak could still be anywhere in the lock system. At least you now know that the unlock diaphrams and lines don't leak. No, it isn't terribly serious and there is plenty of info here on Mercedesshop about how to diagnose and repair the problem.

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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