never a dull day with this car haha

so shes been in the shop and off for about week, i went to drop off some parts today and the air suspension on all sides is fully deflated. i noticed this before tbf but never seemed to have any error codes or issues once the car started.

so is it a slow leak? and will it be from a shared component if all the sides are doing it, ie air pipes/air reservoir.

or can 1 strut leak and also do the rest?

or since the cars been rested for the week did it just deflate its bags cause no need?

The fronts and rear axles are controlled by their own valve blocks so there isn't a common point of leakage between them.

If all four corners are on the bump stops that suggests the EAS module has decided to do it. Usual check is to get it back to the normal height and then take the EAS fuse out. The system does self level downwards over time, as we know, so there may still be a sign of a leak somewhere if it's been sat for a while and self levelled down. Taking out the fuse will check that and also show if a single corner has a leak that might have led to the self levelling downwards.

If the EAS has put it on the bump stops then there is a failure mode associated with that - if two height sensors give spurious readings so that the EAS ECU can't figure out what's going on, it defaults to the bump stops in order to be safe - it's safer than driving around with one side at access height, the other at off road height for example.

So first stop is to raise it to normal height and then take out the EAS fuse. See what it does next. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

okays, currently the supercharger and manifold is off when it goes back together ill stick it back together. but its not on bump stocks(...yet), more like its in lowered mode.

also unsure if unrelated but when going in access mode its being shooting to extended. am guessing it thinks something is blocking it but nothing is, so maybe a height sensor is knackered? cause sometimes it does it fine

Going back up to extended height is a sign of a blocked compressor exhaust valve. Otherwise, a height sensor might be dying as you suggest. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

The computer self levels when parked.
So if one corner has a leak, it will drop all corners to a similar level, and then repeat every ~6 hours

Another thing that can fix the car being stuck in extended mode is recalibrating the suspension, but its sensible to do that once the leak has been fixed.

Once you get your car back, you can remove a fuse under the bonnet to stop the self leveling, and then in the morning you can see what corner is leaking

i was hoping i wouldnt have to deal with the air bags ever honestly if its one of them i may just do all 4 and forget about it. then do the air reservoir cause its looking rusty af. the compressor is thankfully already upgraded to the AMK one

Another fault cause when going into extended mode after selecting access mode are failed dampers that are no longer able to be compressed. This therefore simulates the vehicle being grounded on an object.

I had this on my L320 and I worked out it was the offside front damper at fault. I replaced the complete strut assemblies and it was problem solved.

With a diagnostic tool, monitor the height sensor values when moving from normal to access mode. If you notice one corner stop when all other corners are still moving, you can likely conclude a failed damper. Kev

MY2014 L405 RR Vogue SE 4.4 SDV8 in Corris Grey
MY2010 L320 RRS HSE 3.0 TDV6 in Stornoway Grey

Mgr it may not require damper replacement.
The seals may need changing in the valve blocks. £15 on ebay

since am a nutter who bought this car at 130k with no service history, is there a way to tell if the struts/bags have been replaced?

Have a look at them. The manufacture dates are printed on the white label stuck to the aluminium shield.

Don't just throw parts at the car though. Work out what the problem is first. Kev

MY2014 L405 RR Vogue SE 4.4 SDV8 in Corris Grey
MY2010 L320 RRS HSE 3.0 TDV6 in Stornoway Grey

oh definitely. if its the valve blocks ill be buzzing. but if the struts have been replaced recently then it would rule them out pretty quickly.

i did manage to get hold of the mechanic who used to service this car a while back tbh he serviced it all its life said something to the effect of it wouldnt of made it to this mileage if it wasnt looked after.