This morning on my way to work I had this weird sound coming from 'inside' my vent. I assume it's the motor. Here's the recording of the sound, because I find it very hard to explain... https://www.vocaroo.com/i/s0H7VkA7lwRD

I tried turning it off / on, AC on/off, faster/slower, other directions but the noise remained the same. It sounds like the noise is coming from the top center, right under the wind shield..

It was very cold this morning, no snow, but could it be possible that ice has gotten inside of the vents and melted which could've caused this noise?

Vehicle: Audi A6 C6 4F (2005)

  • Link is not working
    – Granny
    Commented Jan 9, 2018 at 11:58
  • @Granny how about now? -- Works fine for me :x
    – Paramone
    Commented Jan 9, 2018 at 11:59
  • It is! It almost sounds like an exhaust leak. Have you listened in the engine bay?
    – Granny
    Commented Jan 9, 2018 at 12:00
  • @Granny An exhaust leak? Hmm.. The quality isn't great, sadly.. but instead of the 'usual' wind noise.. there's this deeper, more motor-y sound. I just can't figure it out.
    – Paramone
    Commented Jan 9, 2018 at 12:02
  • 1
    @Granny The description of that guy does match mine a bit, but my noise continues even if its cold or warm. It’s still a great link! Thanks!
    – Paramone
    Commented Jan 9, 2018 at 12:17

1 Answer 1


Doubt it is ice getting into the vents. If it were, then you would have a leak when the temperatures are above freezing.

In extreme cold things contract. It is possible the bushings in the blower motor have contracted ever so slightly that when the motor is running, there is just enough clearance to allow some slight vibration.

Or it could simply be the duct connections within HVAC system has contracted in the cold and are allowing vibration to be heard instead of absorbing it normally.

If the noise does not go away after the weather warms back up, it could be the motor may just be going bad.

  • Oddly enough, most of the noise has indeed faded making it unnoticeable unless you actually mute the music, blast the fans and really pay attention. It's roughly 20 degrees Celsius right now, while it was around 5 degrees back when I posted. I haven't really figured out what it was and didn't do much about it, to be honest. You have my +1 tho ;)
    – Paramone
    Commented May 10, 2018 at 6:39

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .