AC Noise

Could be a bearing in the compressor, possibly due to low coolant.

Talking to others, it seems some cars are prone to gradual coolant loss in A/C systems. How gradual seems to vary. We had an Espace which didn't seem to lose any in 13 years. Our Honda CRV needed topping up after about 10 years. I've heard of far shorter periods. I know someone with a VW which was low after a couple of years and needs topping up again after another couple but VW insist there isn't a leak.

I had an Avensis that never needed topping up in the 7 years I owned it. Other cars: Vauxhall Corsa and Vectra, Skoda Octavia - none ever went more than 2 years without needing re-gassing. The Corsa only lasted about 6 months and the main dealer tried to re-gas it several times under warranty in its first summer - after which it needed re-gassing every summer for the next 12 years.

The pressure valves are a source of undetectable leaks, it's where the pressure gauge fits with an o-ring fitting. The caps should have o-rings, if they don't find some that do.

my focus is 18 and the air con is pefect and has definitely never been regassed or topped up. The air con is never intentionally turned off.

My 04 reg Focus is (obviously) 14. The AC does work, but as the local tyre place re-gasses and blows debris that has accumulated for £60, is it worth a punt?

Not if it's Kwik Fit.

with a modern ac regas unit , it would be hard to c*ck it up.

I am surprised that a/c places are still so cheap, a cylinder of r134 has gone from 60 quid to 400 in the last two years.

No - ATS.

I've had my 04 Focus since 2007 - and recently had my first puncture with it. ATS fitted a new one for £45 all in, and I asked the guy about their £60 re-gas offer - and he said it was a very good price as the price of gas had recently gone through the roof.

I took it to a/c specialists I and family have used for years, and sat drinking their coffee and watching while they found (a) the system was totally empty, (b) it held a vacuum and (c) it worked fine when regassed. It is still working fine 9 months later. They told me it was not the first time Kwik Fit had managed to c*ck up what should have been a simple regas.

If it was a c*ck-up: Kwik Fit had of course gained the gas they extracted, so with what you say about the price of it...

But how many of the big chains also offer the "free" safety check with every regas where they then find another £100 of work that the customer has to have done?

My 17 year old Focus, which I have recently disposed of, had one regas in its life and the AC was working for all of that time, except it wasn't getting as cold as previously before the regas.

Have you eliminated the possibility that the belt could be slipping under load? May be worth checking the tension.

spraying water on the belt while it is making the noise will show if the sound changes (without any risks)

GroupON has (or had) a special offer at ATS to have it done for half price at ATS the other week. I used a similar deal a year or so back, not trouble.

You get a voucher online, contact your local ATS place and book in.

If you pressure wash them, maybe. But every rainy drive will get water around the engine bay, so they cannot be that precious.

I had mine fail *twice* on the same car within a few miles after washing the engine with a hose (*not* a pressure washer). It was only after the second occurrence that I put two and two together!

Bloody hell, I hardly ever wash the *outside* of my car, let alone the engine!

But more seriously, I'd have thought you could do Mr C's test with a water pistol or garden sprayer without killing the pulley bearings.

Thanks for all the comments. Just back from a £75 Audi AC service - inspection, empty and refill according to the advert. The noise has now gone.

Didn't stop them spending 4 hours poring over the car trying to find the noise after they'd regassed it. They did manage to find £400 worth of 'faults', though ;-)

(And £2.5k for a clutch/flywheel - it's started slipping during mad acceleration - but not noticeable normally. So I'll leave that one for a bit)