Question about 2003 BMW 325

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Air sucking noise from below the intake manifold.

Just bought a 2002 325i. The car runs great, no engine light. The air induction sound seems a little loud on easy acceleration, I hear an air sucking noise coming from under the intake manifold. any ideas what might be causing the noise?

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Look for a vacuum hose that isn't hooked up

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Once you find the site of your leak the fixes are pretty easy. From what I have read recently alot of people seem to be getting away with just tightening bolts this winter. I dont know if the sudden change in temp or just everyones cars seem to be about the same age.

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