air suspension went out with no warning!
 

just enjoying the day running around houston even had the jag detailed. after i come back from a store i start driving away i see a light with a reading. "car to low" then another light with a reading "air suspension fault" it looked like it was just the front of the car sitting low. but after its been parked, the back dropped too. now it looks like a low rider. the problem is i don't know where to start looking...

IF all air springs are not filling, it is probably the compressor not running to fill the reservoir since that is the most common failed component. Less likely it could be the control valve unit that regulates the amount of air going to the springs. Check fuses, listen for the compressor running and check out the numerous air suspension fault threads on this forum for lots of helpful advice.

The air suspension module (ASM), tries to keep the car level at all times, and relies on height sensors front and rear to do this, 1 front, 2 rear. Front springs are controlled together, rears independently.

So, if the front height sensor starts to give a duff signal the ASM could lower the car. Then the leveling will cut in and the rear will lower, but the rears are OK so the signal from them will tell the ASM that the vehicle height is out of limits, (too low in your case).

You need to get the fault codes read and translated. I have to say it looks like a height sensor problem, not a compressor one.

i did find some threads after looking deeper and gathered some knowledge on this topic. after just checking it out i came to the conclusion i lost an air spring. i can hear the compressor working. the driver side lays lower then the passenger side and from what i get it does make sense why the lower end of the car dropped too being the ASM is trying to level out. i have my insurance coming out monday to check it out. i thing I'm just going to have it converted from the air suspension. i don't want to have this headache again later on down the road. if one air spring failed I'm scarred that the others might start failing. i don't want this costly problem reoccurring. thanks guys for your help!

Is the car still too low, or has it self-corrected itself now ?

Remember, a leaking spring unit will always leak, and the ASM will not be able to keep the car at the correct height at any time, so if it has self-corrected, it indicates the problem lies elsewhere, maybe a duff front height sensor.

I would not abandon the air spring system before it has been thoroughly checked out, at least. Air springs are available on the internet at prices cheaper than Jaguar agents, but are not cheap, just not extortionate.

no, the height has never corrected it self its stays sitting low. the back will raise just a tad but not really noticeable. i looked at some air shocks online and compared to converting to blistens all around is just $300 more thats with my jag specialists installing them. even if the the rest of the air suspension checks out to be fine i would feel foolish to not wipe my self clean of this potential reoccurring trouble. i would end up kicking myself in the ass if the other goes out and 300 more dollars would of stopped it all.

While the potential is always there, not all Jag systems fail or fail completely. I am sure you have seen the Arnott replacement air springs as well as the coil over conversion threads here. It is no surprise the coil over conversion vastly affects the ride quality. As Frasier has commented, you may want to think really hard before giving up on it.

true, i know i'll put more thought into it. I'm having my insurance adjuster come and inspect/estimate this monday. so i have plenty of time to read more threads then hear what the jag techs have to say when they check the suspension sometime this coming week.

What is really odd is that apart from the compressor, most owners here in the UK don't seem to report many problems with the air suspension on "the other" Jaguar forum based in the UK. My local independent told me they have never replaced an air spring. Maybe its our damp climate !!

No doubt in more tropical climates dry rot is very common. Rubber seals here in the southern US often only last up to 5 years.

I wonder how another large market, the Middle East, fares.

How do XJs' do in california weather? I'm thinking of getting one.

It should not be forgotten that steel springs break. However, replacing them is normally fairly cheap. I think what puts so many people off air springing is the expense of replacement parts. Of course this has a lot to do with production volume; as a niche medium in car suspension, the cost will always be higher than steel springs. Why the shock has to be part of the unit puzzles me, it makes each unit cost a helluva lot to replace. The shock part should be separately replaceable.

Well my car is now 9 years old and OK so far, but fairly low miles, (55k).

Hell, why did I say that !! A hostage to fortune if ever there was one. I'm knocking on wood right now - Tap, Tap, Tap.

Actually, my suspension has not been totally fault-free, having needed an exchange compressor, rear lower spring unit bushes, and rear lower wishbones, plus a roll-bar link.

As a Sport it has quite hard suspension; a trip around our beautiful Derbyshire Peak District today on very lumpy and potholed local roads showed me how hard it really is. I would rather have had normal, (comfort) suspension, but the car was too good to miss at the time. Its fine on motorways, and autobahns especially.

with just here in the few days of posting my air suspension problem I've seen more than what i would like with air suspension problems. even if my jag shop says everything is great, it will do more convincing than that from them to not convert my suspension.

Is your Jag shop in Houston the main agent or an independent ? Independents will normally be able to look after your air suspension at much less cost than main agents. I would not rush to convert to steel coils unless you need a lot of costly parts.

Note: the ASM tries to keep the car level, so its just matching the rear to the low front; there ain't necessarily a problem at the rear.

I have an 06 XJL with low miles (26k). How can you tell when the system is starting to go out? My 06 is starting to lower more evidently when turning off.

yes my car is in a shop in houston its jag and land rover specialist called motorcars. i wouldn't say I'm rushing into the conversion its just the practical think to do.
i know the ASM is lowering the car to try to level it out. I'm just saving myself an inevitable future headache.

@ williamsinhb sounds like you have a slow leak coming out from some where. as your driving the air system keeps the car up but when you turn off the car the compressor is no longer working thus making the air escape and making the ASM to let out the air from the other shocks to level out making your car have a low stance. this is "my" theory at least.

A couple of reasons.

First, as Frasier pointed out in a recent post, the air ride suspension provides several sophisticated benefits over conventional shocks such as load leveling, lowering at speed for better aerodynamics, compensation for different road surfaces and compensation for cornering (less body roll).

Second, based on what others have said the car felt like after they converted to coil-overs. Something about increased body roll, softer ride and handling.

Something else to consider, if you have HID headlamps, the active suspension addresses leveling as a courtesy for oncoming traffic. Of course some may not care about dazzling other drivers.

Anyhow, I am not telling anyone not to do it and if all original shocks need replacement, it might be a good option. But just because relatively inexpensive component failed does not mean you should jump to spend more money to "dumb" down your ride. My two cents...