Air Con strange noise?

Kerplunk · 29 Jul 2010 at 18:28

Hi Guys

On my Audi A3 when I turn the Air Con on there is like a grinding noise coming from the engine, doesnt sound healthy at all - anyone know what this could be? If I press ECON on the noise stops. It sounds like it could be coming from the left hand side of the engine (when I open the bonnet)

I doesnt do it when the engine is off.

Cheers for any help in advance

hohum · 29 Jul 2010 at 19:41

I'd imagine it could be the bearings on the compressor pulley making that noise, although I'd take it to a garage for their opinion regardless.

iaind · 29 Jul 2010 at 19:43

Got to be the compressor really, its the only mechanical bit in the AC system

Moeks · 29 Jul 2010 at 19:51

They can do this when they are low on gas believe it or not.

iaind · 29 Jul 2010 at 19:52

Guessing because the refrigerant is also the lubricant - so I'd try not to use it in the mean time!

Moeks · 29 Jul 2010 at 20:06

Yes the R134a contains lubricants for the system.

mjt · 2 Jul 2014 at 20:11

Mine sounds like a diesel and then the noise almost completely disappears when I turn off the aircon.

I thought it was the chain slapping or something as mentioned in the Audi thread.
Aircon blows cold but I guess a regas isn't a massive amount if money so I might as wel refill it and see if it goes away.

I can still hear the diesely racket at idle though when the aircon is off... Thoughts?

andy_mk3 · 2 Jul 2014 at 20:30

Moeks said:
Yes the R134a contains lubricants for the system.

Out the bottle there's no oil in the gas. It's added during a recharge

RJC · 2 Jul 2014 at 20:35

The only part which requires lubrication is the compressor.

mjt said:
Mine sounds like a diesel and then the noise almost completely disappears when I turn off the aircon.

I thought it was the chain slapping or something as mentioned in the Audi thread.
Aircon blows cold but I guess a regas isn't a massive amount if money so I might as wel refill it and see if it goes away.

I can still hear the diesely racket at idle though when the aircon is off... Thoughts?

It might be worth having a go at getting the system charge checked, but this does not rule out possible compressor issue, but try a independent A/C specialist rather than a Kwik Fit service depot, a independent should be able diagnose system better.

acemastr · 2 Jul 2014 at 20:36

Air con compressor clutch gone? the belt will always spin the pulley/clutch but with load on the compressor it'll probably be more noticeable.

pepsilol · 2 Jul 2014 at 20:36

Any longer and that compressor will seize up sending crap through the AC system. You can't flush condensers nowadays either.

mjt · 2 Jul 2014 at 21:20

pepsilol said:
Any longer and that compressor will seize up sending crap through the AC system. You can't flush condensers nowadays either.

Care to expand?

I'm not 100% convinced that it is the compressor. I can still feel rumbling and vibrations when the air on is turned off.

Deleted member 66701 · 2 Jul 2014 at 22:18

hohum said:
I'd imagine it could be the bearings on the compressor pulley making that noise,

This.

I have the same noise on my Scorpio Cosworth. Been doing it since I got the car - they can seize within a few miles or go on to do another 20k miles with the noise.

I'm not too bothered on mine as the aircon is on it's own belt so if it seizes I can just cut the belt off and continue on my way and get it replaced at my leisure.

If the aircon shared a belt, then I'd get it sorted.

mjt · 3 Jul 2014 at 11:12

Popped in to local Audi dealer- he reckons aux belt tensioner.
Makes sense, it's what I thought the other week.

Turning off the air on means less strain but you can still hear it faintly.

mjt · 7 Jul 2014 at 18:32

Noise is getting worse, so popped into a local Audi dealer and the mechanic was pretty sure it's the AC compressor.

I'm currently in Sweden and they quoted £1500 for compressor, condenser, etc.

Don't really feel like bending over for that, so it'll have to wait.
Worst case scenario if it breaks - I get bits of AC compressor in the whole system and need a new radiator or something?

Dr Who · 8 Jul 2014 at 06:36

mjt said:
Care to expand?

I'm not 100% convinced that it is the compressor. I can still feel rumbling and vibrations when the air on is turned off.

The clutch pulley still turns with the AC off as the belt is still turning. The clutch isn't engaged so the compressor isn't turning.

Likely the clutch is the problem.

pepsilol · 8 Jul 2014 at 10:34

mjt said:
Noise is getting worse, so popped into a local Audi dealer and the mechanic was pretty sure it's the AC compressor.

I'm currently in Sweden and they quoted £1500 for compressor, condenser, etc.

Don't really feel like bending over for that, so it'll have to wait.
Worst case scenario if it breaks - I get bits of AC compressor in the whole system and need a new radiator or something?

New condenser, evaporator, compressor and flushing the system.

IMO, stop using the AC, buy a 2nd hand compressor, flush the system , recharge and done.

2nd hand compressors are usually dirt cheap

http://www.ebay.co.uk/itm/AUDI-S3-A...arts_Vehicles_CarParts_SM&hash=item4ad7cc7cb4

Air Con strange noise?

Deleted member 66701

Deleted member 66701