Strange noise from centre console

[SuperbTWM]

4 hours ago, tubbytommy said:

for all you ac know it alls

read the section on the components

i quote

"the compressor is fitted with a clutch that is activated when the system is switched on. The internal parts of the compressor start to turn via the engine power and pressurizing the refrigerant."

ie. it is NOT on all the time )

 

https://www.2carpros.com/articles/how-a-car-air-conditioner-works

This is how air con worked in the 1990s and early 2000's

 

This is how its done now:

 

https://axleaddict.com/auto-repair/Variable-Displacement-Compressors

[Aston_Bodger]

If that's how he thinks it works, well I don't want him anywhere near my car thank you very much.........end of, I'm not wasting my breath any longer.

[phillip]

On ‎14‎/‎07‎/‎2017 at 09:15, Inex said:

I have recently had issues with my AC system and I still do - however I have had the noise and now its gone. It seems to me that it happens when the AC system is low on refrigerant but not completely empty.

 

Mine is leaking and now it leaked out almost completely and the sound is gone...  You can only start hearing when the AC pressure is within a certain range.... At some point it gets so low that you can barely hear the sound...

 

If you had posted this 2 weeks ago I could confirm with an identical video....  :( I am booked for Tuesday for yet another AC investigation....

 

See if you notice any drop in the AC performance.... The way it sounds, it will leak out in a few days .... for how long have you had this?

I first noticed it about 2 years ago, but as it only happened occasionally and wasn't very loud, I decided to leave it and let it develop.

It has become slightly louder over recent weeks, hence my reason for posting it on here.

However, I did almost 200 miles in it yesterday and when stationary could hardly hear it and this morning it didn't do it, albeit I haven't had the aircon on for a couple of weeks now.

[Olivia7]

On 6/30/2017 at 12:01, simion_levi said:

Turn aircon off (just aircon, leave the fan speeds alone). Does it disappear?

 

Hi Simon.

 

I also have that churn, churn, churn noise, but only with the aircon OFF.

With the aircon on I have a different noise. It sounds like someone sucking the last dregs from a can through a straw.

Could you give any advice please?

 

I also have the sound of a cow/moose when the engine is switched off.

 

2008 Octavia 1.9tdi with about 140,000km

 

Thanks.

Edited 5 September, 2017 by Olivia7

[simion_levi]

If it is only occuring when air conditioning is switched on then it could be related to the volume of gas in the system. A certain noise seems to occur when it is a little low (but still functioning). So a regas may fix your can/straw noise. The system should be pressure checked before they refill, so you'll likely become aware of any significant leaks and be able to deal with those at the time.

 

But if it is making sounds with aircon off then there are other issues. Turn the fan off just to eliminate that (if it is the fan being noisy then you can drop the blower unit out from under the glove box fairly easily to remove debris & clean - or replace the unit).

I suspect it may be noise from the compressor though. Your actions then should be directed by your attitude to risk and your tolerance for the noise. If you first inspect the centre bolt on the compressor, the condition of the auxillary drive belt and are also not of the opinion that the compressor is about to seize up imminently, then you could choose to just regass to (hopefully) eliminate one noise and just continue to monitor the other.

[Olivia7]

Thanks for all the info Simon. A lot to take in   but I do appreciate it very much.

 

I think from what you said above, it sounds like an issue with the compressor or belt.

 

With the fan off, there is a sound like a washing machine going around. A slow, low, Churn, Churn, Churn............

[Ionutpancu]

Hello!!

I have a Skoda Octavia and have the same problem same noise problem, I know this topic is old but wondering if anyone find a solution for this problem, thank you

[J.R.]

I am ignoring the spat about how the aircon compressor works.

 

I listened to the video and thought - FINALLY i KNOW ITS NOT JUST ME, THATS EXACTLY THE NOISE I HAVE!

 

It is aircon/climatronic related and I have 2 facts on my vehicle to back it up although mine is the opposite of the person who says it makes the noise with the aircon off.

 

My car never made the noise till I finally got the aircon working after replacing the pump control valve, pressure switch, recharges and finally the compressor, once it started cooling then I had the noise although the noise happens at all temperatures because I believe the aircon is active as a dehumidifier even at heating temperatures.

 

I can make mine go away by pressing the ECON button which stops loading the aircon circuit, put it back to auto and the sound returns, its not loud, I can only here it when stationary at traffic lights when the heater fan is on the lower settings.

 

To the OP try the ECON/AUTO buttons to see if you can make the noise come on command, I cant tell you where its coming from or how to cure it but you are not alone and I take comfort from having heard the noise from another vehicle.

 

I had previously described it as a cyclic noise like heard from a chimney when the wind is blowing.

[J.R.]

Churn churn churn is a good description, I also have the sound of a cow drawing uts last dying breath when I switch the engine off, its like a bovine sigh I'm failry sure its some kind of reed valve or membrane oscillating while the vacuum is being bled off, I dont think it should do it because logic dictates that the vacuum should remain in case you need the brakes if the car moves, handbrake fails etc so I am guessing that later down the line i will have either brake or actuator control problems and the faulty valve or connection will be revealed.

 

Its why I am also obsessive about knowing what strange noises are, often they are harbingers of problems to follow, forewarned is forearmed!

 

Re the aircon gas pressure, mine made the noise immediately after a recharge, I check the pressure fairly often with a guage set and via VCDS and it does not appear to have lost any significant amount or refrigerant yet.

[J.R.]

Oh alright, I will join the fray about the mythical aircon compressor clutch as the person is so forthright.

 

Having stripped down and changed compressors on both the MK1 and MK2 Octavias I can confirm that the MK1 has an electro-magnetic clutch which likes self destructing and the MK2 has a variable displacement compressor, no clutch but a solenoid valve that regulates the output, took it all apart and it was beyond my comprehension understanding how it all worked and then it flew apart into loads of fiddly pieces and like Humpty Dumpty that defied my attempts to put them back together, a clutch was not amongst them

 

There is a shear plate however so that if the thing seizes internally the pulley can freewheel like my MK1 one did after I removed the broken up clutch plate.

[SuperbTWM]

44 minutes ago, J.R. said:

 I also have the sound of a cow drawing uts last dying breath when I switch the engine off, its like a bovine sigh

 

I know exactly the noise you are describing as I have heard it before on some of my cars, i'm 99% sure it comes from the magical black box where all the valves are incorporated into with all the pipework going into it, so it is something to do with the vacuum.

 

It didn't do it every time I shut off the car though

[Phil86]

Hi guys not looking for any arguments ,just got the mk2 octavia and it is making the same noise as above .I have had the heater motor changed but still making the same noise ,more so when  I turn the aircon off. Is this a major problem that needs to be rectified asap ? Thanks guys 

Phil 

[Admir]

my octy mk2 1.6tdi does the same wuh wuh wuh, called a mechanic, he said turn the climate on and leave it on it will go away, don't do anything to the car. 2 yeras later the wuh wuh is much less occuring, when it occurs i just turn climate on and drive happy...