Audi A4 B5 A/C compressor

[minny]

Is there any way to test if it works on the car?

I bought this Audi Avant begining of June, when I did, I noticed the A/C belt was not there, the previous owner had no knowledge of it; So I assumed the AC wasn't working.

However, the next few days I drove as normal, hot weather, blowers on. When I had the blowers on, especially on low, the air coming out was quite icey, way more colder than the blowers on my old A4.

Naturally this confused me a bit, it touched the valves on the refridgerant inlets and the AC seems gassed.

So i am wondering if the AC is infact working, but leaving the belt of to improve fuel economy or they have left it off since compressor has failed. Naturally I don't want to go to the very great expence of having the car degassed and take the compressor off just to find it works fine and have to pay for it to be regassed; let alone fork out for a new A/C compressor at £150.


Also of interest I scanned with vagcom, cleared codes, and scaned again and got the following twice: Air Flow Flap Positioning Motor (V71) 41-10 - Blocked or No Voltage - Intermittent.

I tried to reset these flaps with VCDS, but for some unknown reason when I went in to Address 08: Auto HVAC to do this, nothing was available, even though the car reads it and reports errors, I cannot reset or do any out put tests.

On the second scan the above was the only error reported.

Thanks.

[FrenchAudi]

There is no way the aircon can work with the compressor belt off.

Are you sure it is the compressor belt which is missing?

If so, before you replace the belt, check the compressor is not siezed, or you will shred the new belt and possibly do further damage.

With the engine stopped first check the compressor drive pulley turns freely. There should be no resistance.

Next, turn the spring clutch plate at the front of the drive pulley. This is fitted directly onto the compressor shaft and should have some resistance to turning as the pistons (usually five of these) move up and down. The shaft turns a swash plate, to which the piston rods are connected by ball joints. If the compressor has been run with little or no oil the ball joints and pistons sieze, usually resulting in rapid destruction.

If it is impossible to turn the clutch plate the compressor is siezed and has to be replaced or repaired.

As you seem to know little or nothing about air conditioning I suggest you get someone who knows what they are doing to remove the compressor and make necessary repairs and adjustments, or you will do more harm than good. Unfortunately, in my experience, these are a bit thin on the ground. At least one less since I retired.

[minny]

Yes it's the AC belt, i have spun both the compressor pully and the, I assume tensioner, and they both rotate freely.

I did try and turn the clutch plate, and it didn't move freely so i left it, seems I may need to put a bit more force on it, so tomorrow I will they and turn it. I did buy a belt today, so it was a good job I read your reply first.

I suspect it might not have had a belt on for ssome time, so even if it did work it might be seized.

It's very odd since the car has obviously been well looked after and maintained.

First AC car i have owned, so know nothing.

Funny, you mention oil, there does seem a small drip of oil on the bottom of the compressor, but I thought that was coming form else where and working it's way down, didn't know they had oil in them, so i can look for that as well.

I can get a brand new compressor on ebay for £150, it's the gassing and regassing, plus probably labour that is probably preventative.

thanks for your reply.

[MiniMental]

£150 is a bloody good price! Most motor factors I know they're still over the £300 mark. V71 flap is a common fault on all vag b5 platform cars afaik and is a nightmare to sort. Simple I enough, but remarkably awkward to reach as its right up in the dash. It's the flap which switched between external/recirc. My Passat has this issue, can hear it clicking when ignition is on and engine is off. As above, your AC won't work with no belt. Period, degassing/regassing shouldn't be too expensive to get done if you have a chat with a local garage about its get it degassed, change the parts yourself and the get it redone,

If it was me, I would put a belt on and try it. Iirc It's a standalone belt and if you leave the tensioner slightly slack, it will just slip if its seized up. A belt is about £6, not a bad price for a test. At the end of the day, if your going to replace the compressor if it's broken anyways, your not gonna lose anything by testing it.

That is just what I would do by the way, what you decide on is up to you lol. Had mine recharged by a mate last month, car is like a freezer now lol. Good luck.

[minny]

I thought it a good price, £154 plus £9 postage there's quite a few actually on ebay.

I've done the heater matrix twice on an Audi 80 and A4, so I've had the dash out twice, time consuming but straight forward, though i have read it can be got via the glove compartment.

I got the belt today for £7, I'll try and move the clutch as advised above, then I'll take your advice, slap it on and see what happens.

The car is immaculate, pulls like a train, does 60 miles per gallon around Matlock in Derbyshire, which is very hilly, BUT, it has 207,000 miles on the clock so i'm a little concerned to spend a lot on it, for all i know it could last another 10 years looked after well, could go tomorrow.

[minny]

So I went to put the belt on, but was stoped dead in my track as when I noticed the entire bottom strip of fins of the condenser infront of the radiator was detached and lying on the bummper.

There doesn't seem to be any leaks or aything coming from this, can it be run? or is it a new condensor.

[MiniMental]

Run it. I pulled the top and bottom strip off mine (they were half off) condenser will be fine. 207k is just about run in maybe... My Passat is on 131k and goes like **** off a shovel. V71 flap can be done through glovebox if you have small hands lol. I don't.

[minny]

Run it. I pulled the top and bottom strip off mine (they were half off) condenser will be fine. 207k is just about run in maybe... My Passat is on 131k and goes like **** off a shovel. V71 flap can be done through glovebox if you have small hands lol. I don't.

Oh, good, that's very reassuring.

Mine pulls like a train, way faster than my old petrol B5 with 124 BHP, this has only 115, i can drive constant in 5th gear up slack hill (14% gradient) and then accelerate; maybe it's the turbo, been wondering if it's chipped though, apparently this can be chiped to 139 BHP

Beautiful car.

[minny]

So i puts the belt on with a huff and a puff in the heat today and started up.

The belt and the pulley spin round fine and nothing went clank.

Inside it was difficult to say, it felt icy but then, it always did a bit, difficult to say if it was more or same. When on low it did seem to blow a little warm as well as cold, which i never noticed before and I thought I could smell something a little different in the cabin, this could have been my mind.

There is that flap fault which might be affecting it and of course it could need a recharge of refridgerant.

[FrenchAudi]

Sounds like the ac stopped working and the belt was removed to reduce engine load. This is negligible anyway.