| Sporadic Whistle/Whooshing Noise Through AC Vents | |
Had my 4.4 TDV8 for around 7 years now and I've just started hearing a sporadic whistling/whooshing noise coming through the A/C vents. Generally it's shortly after the engine achieves normal running temperature and the A/C achieves my desired cooling temperature but it has also done it hours into a long journey once or twice. Sometimes it sorts itself after a short time out but other times I have found I have to stop it by pressing the Max button to ramp up the blower and again to return to auto mode. Either way the A/C has no problem blowing cold afterwards.
I was curious and connected the GAP tool to check some of the HVAC live values. I was surprised to see many values reported as N/A, including the interior temperature. Some example screenshots are attached. Is it normal for so many values to be unavailable?
 | | Click image to enlarge |  | | Click image to enlarge |
Some other info in case it helps:
1. A/C generally used in auto mode. Face/feet/screen buttons rarely used.
2. Air recirculation button never used.
3. Previous owner had the A/C control panel replaced for unknown reasons.
4. I've never had the A/C re-gassed. Don't know if previous owners did.
5. I've had the blower motor replaced once and the final stage resistor replaced twice.
6. After initial purchase a whistle could be heard through the vents when driving with A/C off above 140kmh. Dealer could not diagnose and I learned to always drive with A/C on.
This video shows an example of the issue. In this case the noise came on after driving for over an hour with the A/C on. At the 3:15 mark I switch on the Max button and once the blower hits full power I turn it off again and you can hear the whooshing sound has stopped.
https://www.dropbox.com/scl/fi/yef5324ndzf...2&dl=0
Any ideas where the issue could lie? 2012 Vogue 4.4 TDV8 automatic (LHD), Santorini Black
2008 Vogue 3.6 TDV8 automatic (LHD), Java Black
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2nd Aug 2025 1:16am
