I think I'm having some sort of vacume problem. Last night I noticed that when I unlocked my driver side door, the passenger side did not unlock also. When I locked the driver side door, the passenger side door locked. Today, the passenger side door would not unlock or lock by using the driver side. I also can't get into my trunk! I don't have a key for the trunk. I never needed one because the driver side lock would unlock the trunk. Where do I start? Shouldn't there be some sort of central locking device? Where is it on my car?(1980 300 CD) I looked for any disconected vacume lines under the hood, but could not find any. I really need help. Thanks, andy