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I have a feeling I'm going to feel stupid with this one, but....

When I open the car door there is noise that lasts for 4 or 5 seconds. It sounds like a little electric motor moving something but for the life of me I can't suss out what it is. Anyone know?

Thanks in advance.

JTR
 

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You're not the only one. I've always wondered about that sound too. In addition to what you described, there is also a faint, high-pitched sound that I hear during that short duration. Would love to know what that is all about.
 

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There are also three high pitched beeps from the rear of the car at various times.
 

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This answer is based on the behavior of my wife's Eos, with the 2.0T FSI engine. But I imagine it's the same behavior for all modern VAG cars.

The "electric motor" sound you get when you open the door is likely the fuel pump starting up to pre-pressurize the fuel injectors. The car does this to make starting easier. It probably doesn't do it if you open the door again after a short time...it's only supposed to do it when the car has been sitting for a while, and allowed the fuel lines to lose pressure.
 

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My wife's fairly old 1L polo does the same!
 

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This answer is based on the behavior of my wife's Eos, with the 2.0T FSI engine. But I imagine it's the same behavior for all modern VAG cars.

The "electric motor" sound you get when you open the door is likely the fuel pump starting up to pre-pressurize the fuel injectors. The car does this to make starting easier. It probably doesn't do it if you open the door again after a short time...it's only supposed to do it when the car has been sitting for a while, and allowed the fuel lines to lose pressure.
Good call. My Subaru would have to wait a second to start as the fuel lines pressurized. I put in a higher flow fuel pump that was louder and you could easily hear it working before it started.
 

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Definitely the fuel pump priming the injectors -- happens when you open the front driver side door for the first time.
 

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I know when I turn the key to the on position (not turn the engine over) in my old audi CQ, you can hear the fuel pump prime. I didn't know the new Audis did that when you opened the door, thats cool!!
 

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Ya its fuel pump. Other cars that dont power up when opening the door will make the same noise when you turn on the ignition. Its always a good idea to let the pump run before starting. Most people wouldnt let the pump run before starting so moving to door activation insures it runs fully before starting.
 
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