Think I've got a leaking strut

[erubus]

thanks for the heads up. I had a look on their website but couldn't find the struts.

I had a bit of a read up through the suspension section on here and have done some measuring. All measurements are from the ground to the bottom of the wheel arch in th centre.

NSF 660mm (this is the one I suspect has a leak)
OSF 698mm
NSR 706mm
OSR 708mm

Then I started the car. The orange warning light was lit on the dash again. It seemed to take ages to go off but the car did eventually lift. After it had settled the measurements were:

NSF 684mm
OSF 724mm
NSR 694mm
OSR 696mm

Then I put it into lift and set it to jacking mode:

NSF 720mm
OSF 760mm
NSR 739mm
OSR 740mm

So, the rear wheels are within a mm or so of eachother in any mode, the front ones differ by 40mm in every mode (40mm lower on the NS) The NS tyre looks to be pretty soft and the drive isn't exactly level so this could easily account for the difference side to side. Now that it is set to jacking mode I should be able to narrow down any leak to an airbag and pipework up to the valve block and should know more. I really need to get someone with VCDS to have some time on this car. I can get the compressor output checked and have a look at the engine as well on startup and hopefully get a better idea of the hot start problem.

gill

[27litres]

Here's what I found in the clearance section:
audi-air-shock-arnott-4E0616040AA

If the picture is accurate it might be the rear airbag?
I don't know what the strut connections look like on a D3...
So check the part number...

Edit:
Just checked ETKA and that part number checks out for a right hand front strut. Right and left are different it seems...
4E0616039AA (and numerous other suffixes) left
4E0616040AA (ditto) right
"For Sports Suspension"

Near side = left, yes? If so you'll find it, but not under clearance!
left strut
right strut


Looks like their "clearance" price isn't all that special...

Check against what our forum sponsors have too.

[erubus]

Thanks for the sleuthing. I think you're right in that the left and right struts are different. I had a look on flea-bay. There are struts (used) for pretty reasonable money, circa £100. I'm starting to think along the lines of getting a newer A8 with the 4.2 tdi. The ticking from the engine annoys me but the thought of stripping the whole engine out and paying hundreds for parts to fix it isn't too appealing. If I'm not keeping the car long term I'm happy to spend less on a used part than forking out for new.

Measurements from this morning for the suspension. NSF exactly the same as yesterday, all the other ones seem to have risen by 5mm. Given the car is in jacking mode they shouldn't have changed at all by my reckoning. Perhaps its the difference in temperature. It was 14 degrees yesterday and 18 today in the sun. cant imagine that small difference changing the height though.

I'm not sure that this proves anything at any rate. I'm going to start running the car in comfort mode and see if it still puts the warning light on the dash every morning. I've always thoght that it looks ridiculously high in comfort mode though, hence why I always run it in dynamic. Still, in the interests of a diagnosis i will put up with it.

gill

[erubus]

Wee update. Ive been running the car in crop sprayer mode for the last weekor so and havent had the yellow warning light back on since. Since the car didnt drop when in jacking mode and doesnt appear to be dropping in comfort I am assuming that there is some cracking on the where the airbag curls back in on itself when its set to dynamic. when the car is sitting higher the crack are getting closed up and are no longer leaking.

I'm going to go back to running it in dynamic and see if the problem returns. That should narrow it down to one of the airbags (I think) If you put the car into jacking mode when its set to dynamic, does it still lift the car up to the lift position or will it lock up the valves in the lower position?

gill