Convince me I'm asking a dumb question, I know the 7P A/S is a closed circuit, but why?

Tony_B

 

Not entirely sure to be honest, maybe because they thought it's a more efficient and quicker way of having air available for height adjustment?

 

it is closed circuit and nitrogen doesnt have moisture compared to 'air' so its used in most air suspensions.
VW dealer cant assist? whats the standard procedure if they have to replace air suspension/components......will have to check the service manual...

 

Yes I know it sounds stupid, but I called so many VW dealers around GC/Brisbane/Ipswich and all of them said they 'don't have nitrogen' or 'we need to outsource it' yet I never got a call back

 

The fitting on the air tank is a low side r134a fitting. You then just need nitrogen which is relatively easy, and a nitrogen regulator that works at highish pressure and is capable of regulating based on pressure and not flow like most of them seem to be. That's the tricky part, but I haven't looked into it too much be to fair. You could probably vac the system down before filling it, but the bags always retain some pressure, so it would be quite involved to fully purge the entire system.

 

Yeah I've read about that, but as I said I'm not too confident doing the procedure myself.

I ended up finding a shop that claims they can refill it, hopefully they end up doing it🙏

 

Update: Took it in today and they looked over the car and said it works in all heights, no error codes etc. Same-old same-old. They said they left it in the highest setting for a few hours and told me it didn't drop down anywhere.

Apparently the compressor occasionally running for a couple seconds while driving or sometimes after parking is 'normal' according to them🤷‍♂️

At least they didn't charge me to look over it which is a rarity nowadays so top marks for that

 

Ah, I had assumed you were trying to I get it filled with nitrogen after having work done on it. What is your accumulator pressure? It can be normal for the compressor to run at times when self levelling, accumulator pressure should be much higher than bag pressure, so the compressor pumps air from the bags back into the accumulator to lower.

 

Its normal..to some degree. Leave it overnight on the highest setting and see if it drops or not.
Mine, before i replaced the bag:

 

Check these fields:

 

 

I noticed earlier today that the compressor isn't just running because it wants to. Occasionally, the front goes up and down a bit, mainly it's higher up when parked on a level surface or on my slightly uphill driveway.

Yet, as soon as I start driving it lowers down a bit, vice versa.

The workshop redid my basic settings and I've redone them twice using @adidas method successfully. I also don't have any jammed or snapped level sensors, nor do I have any codes for them. I'm very confused...

Unfortunately I was busy and didn't have time to check at VCDS today, hopefully tomorrow😅

 

Seems ok but you should monitor these values for a few days to get an ideea. Most important is overall air quantity, if it drops you have a leak. The bags can be seviced in case one is leaking.

 

That didn't explain why the front is sometimes higher though. It goes up and down whenever it wants, and to be fair it holds pressure too, I've never noticed the front sagging (which still has both original shocks)

 

When parked, it has some autolevel feature. It tries to stay straight.
When driving, i dont know, mine does that only when its raised on the offroad level, after hitting 70 Km/h it automatically drops to Normal level and when i stop on a traffic light it raises again.
The same, if you are on Normal level, after speeds over 120 Km/h it lowers to Sport Mode.

edit: when calibrating, make sure you have at least 75% fuel, empty trunk, correct pressure in tyres, parked on a level surface and on Normal mode.

 

Hi Adidas, I'm about to recalibrate my suspension after checking for leaks etc as I said in the other thread made by @chewblekka.

Does the car have to be running or just in accessory for calibration? Everywhere I've read says to do it with 'ignition on'. I assume this means engine off?

Also when you said that the suspension has to be in 'Normal' mode, are you talking about ride height, damper setting or both?

Regards

Amir

 

Yes, I followed your exact steps last time lol.

I can only assume maybe the front raises when parked uphill as the car thinks it might need more clearance to go over something? No clue tbh

 

It will "auto level" for up to 5 minutes after ignition off. After that, the system is disabled until a door is opened/closed and/or ignition is turned on. I'm planning on draining, vacuuming, and re-filling mine with nitrogen tomorrow or Monday. I'll post some pics of the procedure.

 

I'm planning on draining, vacuuming, and re-filling mine with nitrogen tomorrow or Monday. I'll post some pics of the procedure.

Evacuating and nitrogen filling done HERE:

 

Another thing... my compressor has now all of a sudden started running a lot while driving, sometimes up to 30 seconds at a time and is very noisy... this car is starting to make me sick...

Anyway, I have to take it in tomorrow as the suspension is very knocky all round. Even after replacing the rear sway bar bushes with genuine ones, front lower control arms and both rear shocks (and going over all suspension components bolts to make sure they're tight) I noticed that the rear link pin bushes are torn. The front ones are solid as a rock, but I think my upper arm ball joints have some play, maybe even tie rods and rack ends.

I'm not going to do the rear link pins myself as the last time I did the rear shocks the lower shock bolt was the biggest PITA to try line the bolt up again. I truly don't understand how they can make a car so **** to work on

 

Engine off and Normal mode as in damper settings.