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Discussion Starter #1
Hey all, my 2020 A45S is suddenly very loud in S+ mode (not that I'm complaining!) but it has never been this loud! I was driving home from work yesterday and put it in S+ mode just for the heck of it and it was awesome to hear the car like this!
I'm not sure why it suddenly decided to do this! The only thing I can think of is that it was a fairly cold day (11 degrees celcius), and this is the first time the external temps have dropped so much here (I live in Australia where it never gets cold!)

Has anyone else experienced anything similar? I'm not sure if there's a fault/issue with the car that I need to get checked out! Thanks in advance.
 

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Discussion Starter #4
Haven't changed fuel and the sound has always been on. Checked it now, and its pretty loud even on the outside.
 

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I'm taking a wild guess, but perhaps the lower temps cause the ECU to dump more fuel to create the over-run noise? Maybe during engine calibration in cold weather, the pops didn't sounds right unless extra fuel was added haha. Let us know if it goes away when it gets warmer.

Older ECU would inject more fuel at lower air temps (air temp compensation on aftermarket ECUs like MoTeC), though modern direct injection are much more accurate, so I don't think its related to extra fuel for combustion.
 
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