A6 Allroad estate, front end dropping

[Brian Howard]

I have a 2011 A6 Allroad estate and when left parked up, after a two or three days the front end drops. When I start it up the front end lifts up without me changing anything. When it does this the green (car icon, with 'down arrow') illuminates until it has reached height. Then it goes off. When I test the raising and lowering it behaves properly.

I bought this car two months ago, and it's my 2nd Allroad estate. The previous owner spent over £2770 on the air suspension in December 2023 with a non Audi garage and had the compressor, air suspension valve and air suspension spring replaced. 

The F/N/S drops more than the F/O/S and settles about 2cm lower.

When it's parked up, and I open any of the doors there is a quick 'hiss'  from the F/O/S, behind the wheel area. A bit like the air brakes on a lorry. It will do this if I continue to open more doors. It will even 'hiss' when it's parked up and nobody is touching it!

Yesterday, the suspension had dropped as I hadn't used the car for about  3 days and after I had vacuumed the inside and had all the doors open, I noticed that the front suspension had lifted itself up! I had not switched the ignition on or anything. I did not hear the compressor running, but then I did have the vacuum going and it's quite noisy.

The car is quite old and has 168,000 but it is tidy and runs very well. 

I would appreciate any opinion on what the fault might be so that I can minimise the cost of fixing it. 

Thank you.

[Steve Q]

I'd definitely say a leaking suspension airbag. 

[Brian Howard]

Hi Steve. Thanks for responding.

Is there a suspension airbag for each corner then? If there is, and I guess that would make sense, then do you have any idea why the 'hissing' noise is coming from the F/O/S when it's the F/N/S that's dropping?

Is a replacement a big job? 

I forgot to mention that I have had a diagnostic check done by a former VAG technician and no fault codes came up? That's why I'm trying this forum because I can't afford an Audi dealerships charges just to find a fault. 

 

Thank you