What's this noise??!!

[blizake500]

There is a whining/sucking noise coming from the engine on start up. It only makes the noise sometimes. Usually on cold starts. I have attached a YouTube video.

http://youtu.be/5TTQ5JVrXC8

[ahrensNW]

Is it an turbo?

[roguetoaster]

If it "sounds like a sucking noise" it probably is. Since you know that the intake side sucks, the cylinder does the squeezing/banging, and the exhaust side does the blowing you should be able to narrow down where the noise is coming from pretty easily.

[AndrewBird]

Video sounds more like a bearing squealing or something.

[itsonlygeorge]

Starter noise?

[ForcedFirebird]

That's the starter, and that's NOT a 325i - that is a 325e judging by the intake manifold....