View Full Version : Question 'Popping' sound under dash when stopped using Start-Stop

03-08-2017, 08:08 PM

Wondered if anyone can shed any light on a small issue I've noticed with my A3.

With start stop enabled, and the air fans on (i.e. With roof up), when I stop in s traffic and the engine cuts out, I can hear maybe three to four soft pops from in the centre of the dashboard, about a second or two apart.

If I leave engine running, fine. If I switch off the fan unit completely (or when roof is down), fine. I have read elsewhere it could be Hvac flaps, or something else moving... it's definitely connected with the air circulation unit.

The car is a week into a full year used warranty so I've no problem in getting it looked at, as to whether it's an issue they can resolve or look into, that's another matter.


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06-08-2017, 08:27 PM
I now know it's to do with hvac flaps moving around. It could also potentially be a dash-out job, but I'd need to know whether it's a sign they're failing if I were to want the work to go that far...

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07-08-2017, 08:23 PM
Have you noticed it doing that when you turn off your engine at the end of a journey? I would also check the vent operation positions manually and through all vents to ensure they`re all functioning. If so, it may be a characteristic?

16-08-2017, 08:13 PM
Just to close thread off, had car in at Audi today.

They heard the flaps clicking when changing temperature and sorted it by 'adjusting and lubricating temperature flap linkages' that were behind the glove box, even though the sounds were coming from the central area. However it's all fixed now, both when changing temperature and when the engine powers down temporarily.