Newbie with A6 Allroad air suspension problems

[Allroad-CRaig]

Hi, I am new here but not new to VAG and would like some help please.

I Just bought my second A6 C7 allroad ( this one a biturbo ) and noticed that this one has a noisy suspension pump that runs almost every time I get in it (pervious one had for 4 years and never heard it once) The longer I leave the car the longer the pump runs when I start driving it. Usually comes on for 5 to 10 seconds every morning. On my previous A6 C7 I never really heard the pump coming on at all. The car doesn't drop on any corner overnight so the struts air bags seem fine. Any ideas anyone. I have checked every strut, valve block and pump with leak detection fluid but cant find any bubbles.

Can anyone tell me if the pump running daily is normal as I always keep it in efficiency mode and don't adjust the height.

Thanks in advakce

Craig

[KevTrem]

Might be worth checking the rubber mounts for the pump, if they have perished that may be vibrating as the pump runs resonating against spare wheel well. I would expect pump to run to adjust pressure after temperature changes from day to night etc.

[Allroad_2013]

The pump went on our Allroad at roughly 4 years old and it had been doing the same thing as yours for probably two to three months before it failed. The system is loosing pressure whilst the car is stood overnight and then as soon as it is unlocked the pump operates to bring the pressure back up. Eventually a warning light came on whilst driving and restricted the speed.

We pushed Audi / dealer for goodwill and eventually got it done for just under £500 (against a quote of £1800!!). The pumps can be bought on line for around £250 and it looks like a dooable DIY job. Someone on line also does a repair kit for the pumps which is much cheaper, though whether you want to try that and then risk having to replace the pump if it doesn't work is debatable.

[Allroad-CRaig]

THanks for the advice. I susspeceted the pump also. I'm ok with repairs so might get a kit. Does anyone know where I can obtain one from please? Can I also ask if there could be somthing else that could be causing the system to loose presure - Is there a non-return valve that keeps the pressure up and maintains it once the pump has reached the required pressure?

Thanks again its really appreciated. Once I have sorted the fault I will post and confirm what was wrong so others can benefit from my experience.

Craig

[MFGF]

THanks for the advice. I susspeceted the pump also. I'm ok with repairs so might get a kit. Does anyone know where I can obtain one from please? Can I also ask if there could be somthing else that could be causing the system to loose presure - Is there a non-return valve that keeps the pressure up and maintains it once the pump has reached the required pressure?

Thanks again its really appreciated. Once I have sorted the fault I will post and confirm what was wrong so others can benefit from my experience.

Craig

Hi

Bagpipingandy over on the A6 C5 board makes and sells them:

http://www.bagpipingandy.com/

Cheers!

MF.

[Allroad_2013]

Hi

Bagpipingandy over on the A6 C5 board makes and sells them:

http://www.bagpipingandy.com/

Cheers!

MF.

That's the one, couldn't remember his name

[Whippy53]

And he's good. Very good.

[Allroad-CRaig]

Thanks will contact him.

Craig

[Allroad_2013]

Let us know how you get on, particularly if you remove the pump and repair it.

It would be interesting to know how big and complex a job it is in case ours goes again.

[Allroad-CRaig]

So, I decided to replace the pump as it looked like this could be the problem. This was an easy job to do and took an hour tops, I was uncertain that this was the problem so opted for a cheap ebay replacement. The pump arrived and looked identical to the original Wabco side by side, you really couldn't tell the difference. After swapping the pump I found that the 4 rubber mounts that hold the pump onto the frame were worn and very soft so ordered replacements and fitted them once they arrived, again an easy job to do. This made the noise much less noticeable but the pump came on just as much as the old one did. After a few days of noticing the pump running every time I got in the car and coming on long journeys every hour or so it was obvious the pump wasn't the problem. I decided to refit the old Wabco pump just to see if it made any difference - There wasn't any and it was identical, in fact the old pump was slightly quitter if anything. Before I fitted the old pump back I stripped it down and everything inside was in great condition, no wear, rust or moisture anywhere.

I then noticed that back end of the car dropped a little over night so decided to run the car then park it up and take measurements from floor to the wheel arch on the rear. By the morning both back ends had dropped 20mm over night.

So, either both rear bags are leaking or there is something else that supplies the rear end with air that's leaking, possibly the valve solenoid block in the boot? Again I have sprayed all valves and components and found no leak. Any ideas before I waste more money on something that doesn't require replacing?

Your help is appreciated.

CRaig