Its a venting system for some charcoal filter in the rear area.
Originally Posted by blingin96
I have the same buzzing noise. Mine however shuts off in around 3-5min. Not sure what it is. I think it's my electric fuel pump.
Not sure if anyone mentioned, but the famous parasitic drain is usually the blue tooth not shutting down if you have it.
2013 S4 Loaded (and NO RFT's) Awesome is an understatement
2008 MT X3
RIP you were a faithful sidekick and will be missed.
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2000 Jeep Cherokee
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