Well, the cold weather has finally settled in here and my recently purchased '04 XJR is having air suspension problems.

Drove the car to work this morning with no problems (it was garaged overnight). Car was parked outside for about 9 hours as temperatures dropped into the 30s. When I started it to go home, I got a "Vehicle Too Low" red light warning. I did not - at that point - have an "Air Suspension Fault" yellow light.

So, the front end had - in the cold weather, while parked - sagged dramatically.

I decided to take an easy back road home (about 10 miles). Initially, the front end rose back up and the red light went out. Then, a minute later, I got the "Air Suspension Fault" yellow light followed by the "Vehicle Too Low" red light.

The car is sitting in my garage now with the front end sitting very low. Would the fact that the car sagged on its own, while parked in the cold, be an indicator that it's the front air springs that are leaking?

Any troubleshooting suggestions, given the symptoms, are welcome.

Regards,
Odysseus

 

Hi Odysseus,

Welcome to the Jaguar Forums! It's great to have you with us.

Your symptoms are very common and my first suspicion would be that one or both of your front air springs are leaking from their top seals when cold. The top seal is not at the air hose fitting, but rather around the metal plate on the top of the unit in which the ECATS solenoid is centered.

You can test for leaks by spritzing some soapy water around the air hose fitting and around the top seal, taking care not to wet the ECATS electrical connector. Bubbles will tell you where air is leaking.

If a leak is at an air hose fitting, you may be able to simply tighten the fitting just a little more (be very careful - the torque spec is very low and at least one member stripped the threads). If tightening the fitting very slightly doesn't resolve the leak, you probably need to trim 1/2 inch off the hose and install a new compression ring or "olive." There is a Technical Service Bulletin (TSB) on this procedure, and I think it's available for download from this forum. See the 'HOW TO' quick links thread on the home page of this X350 forum.

If the leak is from your top seal (as it is on our front right air spring), the only "permanent" solution we currently have is to replace the entire air spring/damper unit. However, I've been living with mine for two years now by following this procedure: when I start the car in cold weather (at or below about 40F), I try to remember to notice if the red warning lamp is illuminated on the dash and the VEHICLE TOO LOW (VTL) message is displayed. If so, I leave the car in Park and wait until I hear the air suspension compressor begin to run. This can take up to a few minutes. I then allow the compressor to run until it stops (it will run for up to two minutes). By the time the compressor shuts off, the car may have raised sufficiently to extinguish the VTL warning message.

If the VTL message is still displayed, I turn off the engine and wait 30-45 seconds for the compressor to cool. I then start the engine again and wait for the compressor to run, which will usually result in the VTL message extinguishing shortly. On rare days in very cold weather I have had to repeat this a third time, but only before I rebuilt the air suspension compressor.

It's inconvenient to wait for the suspension to charge, but a lot safer to drive the car with the front air springs properly inflated.

If your air suspension compressor has not been rebuilt with a new piston ring seal, that is something you will want to do as soon as possible. It's neither difficult nor expensive, using a new piston ring from bagpipingandy.com (Andy is a member of this forum). See the photo albums in the link in my signature for a photo tutorial on the piston ring swap.

You can download the Air Suspension section of the Dealer Training Manual from this forum at this link:

http://www.mediafire.com/view/7rdkgg...on_Section.pdf

Please let us know what you learn from the leak tests.

Cheers,

Don

 

Thanks for the troubleshooting and workaround tips, Don! I'll see if I have time tomorrow to take a look.

Regards,
Odysseus

 

This might help too, I wrote a whole thread on your options (this is a very common issue as our cars get older and higher miles)

- click the link below to Suspension Options Superthread








https://www.jaguarforums.com/forum/x...thread-111271/

 

So, I just went out - armed with a spray bottle - to see what I could see. The car has been in the garage since last night. High temp today was around 30F and the high temp in the garage was probably at least 40F. Outside temp right now is 20F.

Cranked up the engine and sprayed some soapy water around the air hose and the top seal on both front air springs. Nothing. In fact, the car raised itself up and the "Vehicle Too Low" red light went out!

Took it out for a 5-6 minute ride. All good.

Pulled in the garage and shut the car off. Got out and heard air hissing and saw the front end sinking. Jumped back in, started the car, popped the hood and grabbed the spray bottle. Didn't need it - air was pouring out of the top of the driver side air spring. Nothing out of the right side.

Decision time. I'm inclined to stay with the air suspension (don't ask me why) though I might be convinced otherwise. That leaves a few choices (and thanks to rosskuhns for his Super Thread on options):

• new Bilstein (@ $900 each)
• new Arnott's (@ $470 each but loses the CATS functionality )
• reman Bilstein (I found Rebuild Master Tech on eBay @ $319...I'm guessing there are others)

**Prices are approx as I found them on the web

I'm assuming I can replace just the bad one if I go with a new or reman Bilstein. If I go with Arnott, I'm guessing I'll need to replace both since the Arnott does not have CATS.

Need to sleep on it. Meanwhile, any thoughts/suggestions are welcome.

Regards,
Odysseus

 

It used to be that only Arnott offered rebuilds of the OEM springs, but I think there was thread here that there are several others now offering them.

Search eBay and Google and you should find several alternatives.

Also, while you are at it, you should consider installing bagpipingandy's compressor rebuild kit. If you are at the point that one of your shocks is leaking, you are also likely at the point that your compressor is worn from age and the stress of dealing with a leaking unit. It's very inexpensive, and not a difficult job to tackle, but will give you years of service.

 

Good point on the pump; thanks.

Has anyone installed the rebuilt OEMs from Rebuild Master Tech Air Suspension, Engine Parts & More...? At $320 each the price is certainly right.

Regards,
Odysseus

 

All the firms that "rebuild" the Bilstein OEM units replace the air suspension diaphragm; the shock absorber is untouched. nor the the upper air seal, in fact I don't think this is removeable as it is fixed in position when the unit is built at the factory.

Have you thought of getting a used unit on eBay. If it only lasts a couple of years its probably worth it. If you go the Arnott route, you'll need to replace the front pair. Looking on a supplier here in the UK I see the Bilsteins are on sale for £469, but of course we then have to add on our atrociously high VAT at 20% making the price about £600 same as your US price.

If it were me, now the Bilsteins are available at far lower prices than Jaguar dealers charge, I'd replace the one leaking air. Of course the other could go too, but you never know when.

At least the height detection system seems to be working OK ! Do note Mac Allan's comment on the compressor, but it could well still be OK, so see how it goes. You'll probably also find the lower shock bushes are shot on both sides, so if you're going to do some work, replace these too, they aren't expensive.

 

Hmm. When I called Rebuild Master Tech, they were out of stock on rebuilt units. They said I could send my original and they'd rebuild it. When I was diagnosing the problem, I found air leaking from the top of the air spring, around the the electrical connection. Upper seal? If so, are you saying they wouldn't be able to rebuild it?

Also, regarding the shock itself, the wording on their website led me to believe that they do attend to the shock absorber although I might be inferring something that isn't there:

"The second factor of an air strut failure is the strut itself. The strut is pressurized with fluid, and if the strut begins to fail it will no longer have the same pressure to hold the vehicle. If this system begins to fail one visible sign will be that your vehicle will be lower than factory height." --Rebuild Master Tech

Thanks Fraser. I'll call them tomorrow to dig a little deeper. I'll let you know what I find out. May be that a new Bilstein starts looking more attractive...

Odysseus

 

Needless to say, if the top seal is leaking, it would be possible to attempt to seal it once the main air spring diaphragm is removed. Sealing on the pressure side, (which can be very high pressures when the spring is working), has the possibility of working, but applying sealant externally at the top is problematic, as the air pressure is pushing it away. Once the shock starts leaking damper oil the strut is basically scrap, as they are not repairable. Having said this, they do last a very long time, being Bilsteins, and not Jo Noname !

 

So, can't seem to make up my mind on a strategy to get my front air spring done. For me - since I want to retain the air suspension - it boils down to:

• Buy a new Bilstein ($820 - ouch)
• Get the existing spring rebuilt ($320 and how good is the final product?)
• Swap in a new Arnott ($820pr - lose CATS and need to replace both fronts)
• Possibly find a good used spring

I have one question: How do I know if my '04 XJR has the Sport or Comfort springs? I would have assumed that XJRs would have Sport but I've seen parts listings that show both for the XJR.

The reason I ask is twofold: 1) If I find a good used spring, I'd want it to match what's on the car, and 2) If I were to consider Arnott, their springs are tuned somewhere between Comfort and Sport so, I'd like to have a sense of how they would compare to what's on the car now.

Thanks,
Odysseus

 

Odysseus,

There are colored spots of paint on the body of the air spring/damper units that indicate whether they are Sport or Comfort, but I can never remember which color means which. But Fraser knows and I'm sure he'll offer that information when he comes online.

In the meantime, you may be able to find the information by searching the forum.

Cheers,

Don

 

Red dot is sport, green is comfort.

 

Correct !!

Just to note that unlike steel coils, which can sack-out over time, the air springs are always at the correct height as the system maintains it by getting inputs from the height detectors, and then adjusts the pressure in the spring to return to correct height. This means that one can replace just a single spring unit.

Of course this is all things being equal, like the opposite unit has a good shock with no leaks. The shocks in these units don't really wear out much, but the hydraulic seal fails after a while, although that "while" is a very large mileage, like can be over 200k miles

 

If it helps you decide, I replaced my one leaking front spring with a rebuilt unit several years ago, and have had no problems. About 18 months ago, I used the bagpippingandy kit to rebuild the pump as a precautionary measure as the car hit the 10 year mark. Surprisingly easy to do.

If you want to DIY the air spring replacement, there is a method for doing it without the IDS/SDD computer system. It should be in the "how to" sticky at the top of the forum.

 

Thanks Mac. Would you mind sharing where you got your rebuilt unit? I've found two companies in Florida: Rebuild Master Tech and Suncore. Both are in the $320-$335 range, per spring.

Odysseus

 

I got mine from Arnott. At that time they were offering rebuilt OEM units.

 

Yes, Arnott does not sell rebuilt stockers anymore. I talked with one of their tech's and got the inference that they had too many issues with rebuilds. I decided I wasn't excited that all of the rebuilders are basically taking used shocks and pretty much just putting new air bladders on them - so you might get a shock that had 20k on it from a sunny warm part of pot hole free California...or get one with 150k on it from the rusty midwest.

*for some reason I have a negative opinion about suncore (not sure why?). You might want to search hard for some reviews on their product. (here and on the general interwebnettings).

**As I've reviewed, I'm didn't find the loss of CATS to be a big deal at all, seems more like a gimmick than a legit 'must have' game changer. I thought it was a very cool feature on reading about it, but in real life...not a big deal.

 

I guess I'll start saving up for Bilsteins, mine will be due.

 

I hired a local Goodyear service center to replace the troublesome air suspension system on my 2005 Jaguar XJ8L (I purchased the vehicle on eBay in early 2014) with the Arnott coil/springs, and never looked back. Many Jag owners have opted towards that route. In my opinion, the Arnott coil/springs offer a superior ride in many respects.