Thanks for your input Charlie, I wish I had parts research information for later models so I could look for superceded/ updated components.

My guess is that the Bay Area does not qualify as "arid", so any moisture that may have condensed in your system didn't hurt a thing. Your '04 goes into the "much ado about nothing" catagory, and just aboutanything that lasts 80K of reliable service is a good build in my opinion. The issue then becomes excessive repair cost, so any remedial action that proves to be effective will at least help to increase the lifespan.

I'm stuck for information at present, any additional data of relevance from readers is appreciated. Thanks for yours!

 

There are also a few posts on this forum especially the faults and mechanical sections: http://dandmbr.proboards27.com/

 

Thanks for that, I found it when I researched the jagforums.uk link you previouly shared. I'll go back and look through again, though.Both resourcesare much appreciated.

 

What are all the symptoms of this issue? Is it simply the car won't rise to the correct ride height? After receiving an Air Suspension Fault several times my front suspension is now sqeaking badly.

I live in Chicagoland and the weather has been bitter cold for weeks. Seems like we've had only one or two days above freezing in the last 30 days. As the weather turned cold I started getting sporadic "Air Suspension Fault" errors with the yellow light on the dash. I called the dealer and he said to ignore the error and that it is "simply some moisture in the system" and nothing to worry about.

It's very inconsistent and I never noticed if the ride height was off. Car seems to drive just fine when the light is on and it seems I could sometimes get the fault to occur if I height the gas somewhat hard while the card was cold. As the fault was sporadic that doesn't consistently work and could simply be coincidence.

Now the front suspension is squeaking badly. Sounds like door hinges that need oil. Every bump at every speed causes a relatively loud squeak from the front. I'm bringing the car in for an oil change this weekend and I plan on having this concern addressed then. Any insight before my visit would be appreciated.

It's a 2004 XJ8.

 

Greetings Silver,

No shame on you for missing some information in this rather long thread: I wrote it long by design, to try to chronicle alot of related discussions in one place. You just helped to make it more productive, I hope.

I don't have any answers for you, I have only the same questions. Here's a non-confrontational one to pose to the Sevice Manager at your Dealership:

"If the intermittant warnings are caused by moisture in the system, is there anything you can do to remove it?"

The comment you received over the phone is the first one I've read where anyone has stated that moisture does in factget in the system. I'm still asking that question, and the subsequent question of the effects on all components in theCATS systemif it is proven to be a real-world occurance.

So maybe your Dealership has information that is not widely known...or maybe that was just an off-the-cuff script remark (no insult intended)to ease the concerns of customers with an apparently common problem.

It would be helpful to know:

(1)How many miles are on your 2004 XJ8,
(2) What the answer is to the question about the moisture, and
(3) What action is taken to resolve your noisey front suspension.

Stuff wears out, if a compressor can't make minimum presure in the requisite time when it is cold, then the Air Suspension Fault light comes on. The idea about preheating the incoming air is a logical figment of my imagination to this point, with no practical test. It won't cure a worn out compressor, and perhaps upgrading the componentis the only real solution to the fault warning at low temperatures... or adapting software to delay the initiation of the warning, as Real_Teach suggested.

Speculation:

Your system is maintaining pressure, or you would have noticed the decrease in ride height. So your front struts do not have significant air leaks, which I have been told are more frequent in low temperatures. We don't know if the front suspension noise you are hearing has anything to do with a CATS system fault: and if the front struts are the source of the noise, perhaps they have reached the end of their life expectancy and they are just worn out.

So there is no one "issue", unless this chain of speculation is correct:

" Postulated: As there is no device in the system to prevent moisture ingress, water inevitably collects in some or all Air Suspension systemcomponents. This water freezes in low ambient temperatures, impairing proper operation of the control valves or otherwiseaffecting line pressure. This moisture also causes increased wear and deterioration of sealing surfaces in the compressor and the struts. The addition of a desiccant bottle will prevent moisture ingress, eliminate the possibility of icing, andextend the lifespan of the internalsealing surfaces. Additionally, regulating the compressor inlet air temperature, by preheating in cold climates and by utilizing an interiorcabin air inlet source in all climates, will further increase the efficiency and lifespan of the compressor". Andrew Bernstein.

Don't walk in and throw this at your Service Manager, he knows his job. I don't know anything yet about moisture in the system, these are all just my figments. The question is, what he meant.

 

Thanks for the response. I did leave out my mileage, didn't I? I'm rolling up to 74,000 miles. I bought it in Feb '08 with just over 41,000 miles on it and I put a lot of highway miles on it this year.

Some of you may recall the engine was replaced around 43,000 miles due to a seized cam bearing. That was a fun warranty claim.

The only other odd noise is a clicking that occurs in cold temps - under 40 degrees or so. Seems like it is coming out of the driver's side of the engine bay right by the front window. As it typically happens when it is cold out, I'm too lazy to hop out and try to identify the source. It's a fast clicking - like an automatic watch - a few per second.

It warmed up today to a whopping 27 degrees and the squeaking stopped and there was no fault light. The light only happens about once a week. Maybe twice.

I have it serviced at Imperial Motors in Lake Bluff, IL. The service manager there is Phil and their mechanics seem pretty sharp. His response was instant when I mentioned the air suspension fault. He instantly related it back to moisture and cold weather. He also said I'll continue to see a lot of odd things happen with the car when the weather is cold. The Jaguar dealer in Aurora, IL made the exact same cold weather comment - that XJ8s and cold weather do not get along well together.

I'll keep you posted after my service appointment. One thought though, if there isa leak and the system cannot maintain pressure to set the correct ride height, couldn't moisture enter the system through that leak. My car does settle when parked at night. When I turn it on in the AM the front end will come up 0.5" to 1.0".

 

Well, that certainly suggests there is a leak. Moisture isn't entering there though, it enters with the incoming air every time the compressor runs unless there is a drier to filter it.

 

My car settles at night too. When I start it in the AM, I can feel it raise up pretty fast. I attribute it to parking it in the evening with a warm air system and the air contracting as it gets colder as it has been recently. I agree these cars hate the cold. Definitely ask about the clicking noise. My car gets the same way in the cold and I'm hoping it's just a common occurrance.

I think moisture isinevadable in acompressor. It's a natural byproduct of compressing air. Maybe a pre-dryer will minimize the moisture but it wouldn't eliminate it. All of these trucks and busses have air systems. I believe none of them have a "pre-dryer" for air coming into the compressor. They all have air dryers after the compressor and all of the air tanks are required to be drained regularly(some are automatic). Maybe Jaguar needs to find a different supplier like Bendixwho have been manufacturing these things forever and know how to keep them from malfunctioning in colder weather. Not that it solves the issue for anyone here.A way to automatically dry the compressor internals after the car was turned off would be good but making it withstand the elements like every other air compressor does is probably the best option.
I understand the service life of these compressors is what? 40,000 miles? most people average about 15,000 a year anyway. So once every 2 1/2 years isn't detrimental. Especially if the factory has to pick up the tab on the first one. Who has replaced two of these compressors? If you do it yourself it's cheaper than a new set of floormats.

 

Thanks for that, I don't know anything about trucks and busses. And the only sliver I know about Land Rovers is that their Electronic Air Suspension system uses an air drier with replaceable desiccant beads in their Classic, 4.0 and 4.2 models built from 1994 through 2002.
If LR III and later use a drier, I haven't found info on it yet. Maybe they found a solution for everyone there.

All of the Jaguar Service professionals I have discussed CATS system problems with have generally been interested and supportive of my questions. Not alot of answers, but recognition of the symptoms. It certainly reads like I'm on the same page as Silver's service manager, and I hope to learn if he has any suggestions for improving system performance and reliability.

So I don't really understand why your opinion is so dismissive, perhaps it's because your car is still under warranty and you won't be faced with excessive repair costs on a depreciated car. That's the situation my future customers will be in, and I'd like to offer them better solutions than taking the bus.

 

Link to concurrent new thread, "Air suspension fault" by Heaven

https://www.jaguarforums.com/m_92482/tm.htm

 

JTO-
The only thing I'm dismissive about is that the air suspensionseems to bea deciding factor for many people anticipating whether or not to buy a Jag. I would like for potential owners to feel that the odds are not stacked against them.I think perhaps it'sbecause I run into so many people that have an '80's Lucas mentality aboutJags and think they they are all money pits. I think you're reading out of context here.

On the Land Rovers. Were the air dryers before or after the compressor? I have a Prevost (reason why I refer to trucks and busses) and knowthat the air dryer in it has a dessicant filter after the compressor as do most commercial trucks. The reason I ask is because we are all talking about the compressor having moisture in it and any air dryer placed downstream of the compressor will not remove the moisture from the compressor itself(where the problem is),unless the majority of moisture is traveling from the system back into the compressor. Just a thought

 

Thanks for that, my reading comprehensionis just fine and enables me to interpret something that is accurately written. Or not.

If you go back and read this thread from the beginning, in context, you'll find that I already pointed out the perceived fitment of the reciever/ drier. I'm not going to rewrite that whole section for you too.

Instead, I'll wait and see if anyone can offer some substantive information. Either I will get some response from Jaguar Service, or it's time to buy an '04 and start reverse engineering it to teach myself how everything does,and does not, work. Exactly the point I was making to oldmots, and exactlywhat I had to do togain familiarity with X308 and XK8. Talking about facts is useless, unless I'm talkingwith somebody that recognizes facts.

So thanks for pointing out that you have a 2005 Vanden Plaswhich settles overnight. I'll evaluate that fact in thecontext of all the CATS system deficiencies and failures I'm reading about, and decide if it has any significance. Or not.

 

Silver-
I was browsing another thread and came upon a post by Panels about the ticking when it gets cold outside. I have the same ticking noise in the cold and maybe this is the answer.

 

Enveloped in the mantle of Jaguar etiquette, I would appreciate that a new thread be initiated for the discussion of this apparently unrelated symptom. I'd like to not have to separate the wheat from the chaff when printing out this thread. Thank you for your assistance in this matter.

 

Having just replaced a compressor today, I had a good look at a new one and compared it to the old one,there is no visible or outward difference between a 2004 and a new one other than which parts are painted and which are unpainted. The entire job took only 1 hr in the driveway. Brutal's instructions saved me a lot of time. I drove the car up on ramps and dropped the front portion of theunderscuttle, then removed the fender liner screw in the front upper area and a plastic nut on the liner in the wheel well to allow the liner to be pulledout of the way slightlywhere the compresssor is. I did not remove the front wheel.This gives full access and an easy replacement job. The trick is to remove the new unit from the suspension frame that it comes spring mounted to, then remove the old unit from the frame in the car and install the new unit to the old frame whilethe frameis still in position attached to the bumper. This frame is bolted from the front of the bumper and the bolts are not accessible without removing the bumper cover.
There is a filter on the incoming air that is like a large plastic fuel filter, there is also a large cannister on the output side that is obviously a dessicant drier. The unit also has an exhaust function that can relieve pressure by electronic control.I did not dismantle the unit to see how it worked since I want my deposit back. I will say that the construction is substantial and the unit is heavy. The motor is the size of a Japanese car starter motor.
The air fittings are finely made bronze with double internal o-rings and a tiny squeeze-chuck to hold the tubing in the fitting. These parts are very nicely made, much better than on any other car I have seen.
Thanks to Veffremov for helping me find one for $475, this is way less than anywhere else I could find. When I called the Dealer for a reality check, the $950 they quoted for the identical part took my breath away. If you look at his posts, you can find the address. This part was sold as rebuilt, but as close as I could look, I looked new to me. I hope this clarifies the issue some, it doesn't help explain the short service life, but there you have it.

 

Thank you very much for your post Mr. Caro.

At least now I know that a drier has already been fitted. It might not be effective enough to keep the system dry, or if might be effective enough that it becomes restrictive, but at least I know it is present.

 

After looking at the unit, I realized that the loud exhaust noise from the compressorI sometimes hear aftera drive is actually the compressor pumping or relievingair out the intake (there is plumbing and a valve body arranged on the unitthat would make this possible, I didn't know what it was until I thought about it more), probably to clear the intake andfilter and maybe even to clear the drier. If this is what is happening, this thing is pretty fancy. Its failure in cold weather is still a mystery, I would have loved to open the crankcase to see if the lubrication was drying up. Maybe someone will get one and tear it apart. The crankcase is riveted together, so it will require a drilling job, thus why I left it alone.

 

I keep forgetting to mention that I think theproblem may be in the valve design, but without looking at them, there is no way to be sure. Maybe the valves are just wearing out and getting leaky, and the slower motor rpm in the coldaccents the problem. It probably isn't dirt, since there is a filter, but if they are reed valves, they may have metallurgical problems.

 

Time for some forensics, for sure. If anyone reading this has an old compressor I can buy, please PM me. Same for any air springs or other components.

Mots, getting back to the exhaust noise from the compressoryou heard after a drive, this was with key off ? And I think you had said it was a symptom that you did not notice when you first owned the car?

One more if I may, how many miles on the car? Thank you again for your valuable information.

 

I was looking through archives to determine oldmots' mileage, and came across this post. It should have been included in my original letter, and it was an oversight on my part not to do so:


RE: I thought I bought a good car!!!! - 1/15/2009 6:50:06 AM

oldmots

Super Member

Posts: 198
Joined: 6/30/2008
Status: offline
"If you have no leaks and the compressor is good, you might look at the valve block and pressure tank under the spare tire. Check the connections to the module in the spare tire area. It is possible that ice forming in the valveblock in very low temps is blocking the solenoid valves open and lowering the car. Apply heat with a hair dryer or similar to the valve block when this happens and see if the level is restored. Keep in mind that the compressorcan introduce water vapor into the system during operation and ice may form in sensitive areas."


Since this post speaks to the same questions in my mind, it should have been previously included. I am not the sort who takes credit for the contributions of others and apologize to oldmots and other interested partiesif my omission created that appearance. I'm just trying to work the problem and seek out some resolutions.