Whining noise in the cabin
 

So.. I have this kind of whining noise in the car.

It varies in frequency with the engine rpm and also seems to get less audible the more I push the throttle at a constant rpm.

It’s not LOUD, so if I listen to the radio I can’t hear it, but it’s still annoying..

If I turn AC off (push econ button) the noise disappears, so..

More likely to be the AC compressor itself or a pulley somewhere ?

Car in signature, ‘06 3,0tdi.

It's not the Mrs, is it?











Sorry.

in warm weather I've found the radiator fan runs at quiet high RPM with the AC on that can cause more noise in the cabin, but that is a constant sound that does not vary.

Its a common problem - mine had had it since I bought it and is to do with HVAC fans/flaps which, apparently, requires a fair amount of work to replace. There is a thread which I contibuted to so ill see if I can find it. +++
Edit: This thread touches on it but it does refer to earlier posts on the subject.

http://forum.a8parts.co.uk/showthrea...=ghost+machine

Mine does this. Does my nut in. Was the last thing I thought of. I’d messed with everything before I switched the HVAC off and boom. Silence.

The commonest whining noise is the auxiliary coolant pump, but that stays on even if the HVAC is off so it's not that (for a change!).

Did any of us ever manage to sort this? Still annoys me, (but then most things do).

do you have a video of the noise as i have a whining noise that goes with engine rpm also, i think its engine related ie turbo but can't find the location on the noise

I’ve just tried to capture the noise. Cycling between HVAC Econ on/off.

Not really found a way yet, to get it to be picked up by my phone’s mic.

I'd guess at the magnetic clutch on the aircon compressor beginning to fail, when the econ button is pressed it doest try to engage, but when the aircon is required the magnetic clutch should cause the aircon pump/compressor to drive off the engine/belt. . .

I was think bearings or something internal to the compressor. Sounds about right^

D3 should be permanently driven compressor without a clutch with a pressure regulating valve instead. Still could be making noise when putting load on it.

Dean had this with his S8 and it was the bearings in the compressor. We put a new one on and the noise was no more.

I actually had to label the compressor so I knew it was duff and didn't make its way in to 'good used stock', since you couldn't feel anything untoward spinning it by hand, and the clutch was fine. It was only under load at engine speed that it made the noise.

Just thought I'd add that before we went to France this summer I had the A/C's refrigerant replaced. The cabin was taking 15-20 mins to cool. I'd noticed over the years, it had been taking longer and longer to cool, but once cool kept cool.

The level of refrigerant was just over half of what it should've been.

Now the A/C is noticeably colder, quicker to cool and quieter. I'm not certain, but I think the fan isn't having to spin as fast etc.

Did 2,200 miles over the last few weeks in France and so far haven't noticed the annoying whine.

This could be because I had the wife and kids with me tho', maybe their whines were louder!

I'll have a proper listen tomorrow.