Your car should have the vacuum assist door closing system, meaning you just gently close the door and then the car pulls them shut automatically and silently. If this is not working it might be an expen$ive fix. Same for the trunk, it should close once you just lower it to a "closed position".

They should work just like in this video when you close them:

http://www.youtube.com/watch?v=iH4P7F55ccE

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