Disco 2 Air Suspension: both sides sagging slowly

I've read the 'everything you need to know about air' sticky and a load of other threads but I can't find another one quite the same as mine.

I woke up yesterday morning to find my 2000 ES TD2 D2 sat on her arse - both sides right down. I started the engine and pumped her up to 'off road' height no problem and as soon as I got going she dropped back down to normal level. She was fine as I was using her throughout the day but yesterday evening over about 4 or 5 hours she dropped right down again on both sides.

Same thing again today.

I don't think it's an air bag leak unless both sprang a leak on the same day
I don't think it's the compressor as they pump up fine
I don't think a height sensor problem would cause these symptoms either
I guess there's a leak somewhere that's common to both sides of the system

Anyone got any suggestions what it might be?

To be honest I'm not going to fix it myself and the garage I use is a LR specialist but I'd just like some idea so I know whether it's a small job or a 'wait til payday' job. And if it's an expensive job can I continue to use the car as long as I pump her up before driving?

Air bags! how old are they? mine did this although only 1 was knacked, took ages to find the leak, 1 had been replaced by orginal owner, i replaced both as that's what is recomended, no problems since!

I changed mine for coil springs, and got most of my money back when I sold the compressor!

discodrivercumbria said:

Air bags! how old are they? mine did this although only 1 was knacked...

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If it was only dropping on one side I'd suspect the leak was from the air bag but I find it hard to believe they both went the same day.

wattfield said:

I changed mine for coil springs, and got most of my money back when I sold the compressor!

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I will if I have to but I prefer the ride of mine with air to the ride of my mate's which has been swapped to coils, particularly when cornering on the road.

Higgo said:

If it was only dropping on one side I'd suspect the leak was from the air bag but I find it hard to believe they both went the same day.


I will if I have to but I prefer the ride of mine with air to the ride of my mate's which has been swapped to coils, particularly when cornering on the road.

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they don't always work like that, triggers the sensor and then both go down, not always! but that's just how mine did, i left it for a while as i didn't think that was the way, but if it knacks compressor thats more exspense again, 2 new bags and mine was sorted!

discodrivercumbria said:

they don't always work like that, triggers the sensor and then both go down, not always! but that's just how mine did, i left it for a while as i didn't think that was the way, but if it knacks compressor thats more exspense again, 2 new bags and mine was sorted!

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That would be good news if it's a simple airbag problem bringing both sides down.

Higgo said:

That would be good news if it's a simple airbag problem bringing both sides down.

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blow it up, close the doors with engine running, reach trough the window and press the ride height, when it goes right up spray some warm water with fairy liquid in around the airbags, it will show bubles where it is leaking, also the connections, then you may find the leek, i did, but i had already bought the bags, so was already to do the job, i stuck my bags and got em off easier, replaced with new clips aswell. job done in an hour, i also cleaned and lubed the ride height sensors

Mine has only sat down once, all the way down on one side and half way down on the other.
I say it has only done it once because I replaced both airbags straight away and I've had no trouble since.
Never change them one at a time, do both.

brian47 said:

Mine has only sat down once, all the way down on one side and half way down on the other.

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As far as I can tell (from the two times it's done it in daytime) it's going down evenly. This isn't based on complex measurements (and I live on a hill and park with one wheel on the kerb and one on the road) but I stick my head out of the door every now and again and I don't see one side lower than the other.

brian47 said:

Never change them one at a time, do both.

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Absolutely.

The SLS has the tendency to relevel even with engine off from time to time(LR oddity) so even if only one bag is leaking the other one might follow it on management request... the best way to rule out a leak or management issue is to disconnect the battery if the car i in safe place of unplug(electrically) the 2 air supply valves and compressor when the vehicle is on normal level...if there's no leak it will stay on that level for many days then you know it's a manangement issue, if it goes down with battery or valves + compressor unplugged it means it's a leak...you might get a SLS warning on dash this way that's all

I have had this problem twice. A single leaking spring will cause both sides to go down as the system tries to keep the car level. Beware overusing the compressor because it is designed to keep the system in trim, not inflate it from scratch each time you start up. Try raising the rear suspension next time you park up and you may find that in the morning it hasn't sagged. In the meantime get some new springs. I fitted Dunlop ones which were much cheaper than Land Rover parts. They come with comprehensive instructions. You will need to support the chassis on axle stands and use a jack to manoeuvre the rear axle. The Dunlop connection is slightly different and you will need to remove the brass connector on the air pipe. Once you have fitted the new bags, raise the axle as high as you can on the jack to fool the self leveller into thinking the car is sagging and they will inflate. Not a particularly difficult job. Also worth remembering that the 7 seat D2 MUST have air springs to meet type approval regs.

Same thing on mine, one was leaking but it dropped down evenly.
Buy good quality bags, I think mine were Contitech, they came in Britpart boxes but they were the correct (good) ones.
If your system is ok it should stay up even when parked up for a while, mine wasnt driven for over 8 months and it didnt drop at all (other than the 1" or so thats normal)
Mark

Yes, it was only one that was leaking. Garage reckoned they looked quite new so the leaky one may have taken some damage (I must stop driving over those ninja throwing stars) so they only fitted the one.