I have a 2004 Vanden Plas pushing 168k miles. In the bitterly cold two weeks ago (we're talking -10 F) I got an air suspension failure light, but no noticeable drop. Next day same warning. Then it warmed up and no more warning problems. Ride was fine in teens F.


Very cold again now (down to -3 F last night). Did not drive Jag today and when I got home from work it was squatting on ALL four wheels. I think it's probably the compressor, and to my knowledge none of the suspension parts has ever been replaced. I started the car and after several minutes the suspension had lifted up again.


Question #1: What is your diagnosis?
Question #2: If compressor, better to replace compressor or go for replacement with coil suspension? Struts could fail any time, and replacing with air suspension parts would end up costing way more than the coil over.


Your thoughts ... thanks!

 

Air is much denser when it's that cold. But your compressor seems to be working right? It fills the struts back up. There is a reservoir tank in the trunk somewhere that is supposed to hold air in it to keep the struts from deflating during super cold weather. This is a serious fault in the design of the air suspension parts. I mean does it not get cold in England or something?!!!!???for what's it's worth, it's not all struts leaking, this would be unlikely to happen. As far as replacement of air struts, that's gotta be a personal preference. I have only had this XJ for a month, and have only out 120 miles on it so I can't give you any advise on what it might be, but I am in love with the ride quality of the air suspension...when it works, it's awesome. Good luck.

 

Thanks, Cherry_560sel. It does seem unlikely that all four struts would fail at once, and the compressor does seem to be re-inflating them. I didn't know about the air reservoir tank, but something is not holding air to keep the struts inflated. With respect to replacing with coils, I'm trying to work with several variables. If the problem now is only one certain part (compressor, reservoir tank, something else), then repairing that one aspect may be least expensive. However, with the age and mileage, any of the suspension parts could go at any time. The coil over bypasses all those potential problems and their associated costs that will add up to more than the cost of the coils.

 

You need to get the fault codes read. If one of them is C2303 Reservoir Plausibility Error, it means the compressor is failing to charge the reservoir within the allowed time, indicating it is starting to fail. Cold weather will cause this warning to be displayed, but as the compressor deteriorates, the warning will eventually come on a lot more, even when it's warm weather.

The compressor is the part that lasts the least amount of time in the suspension system. You can buy a piston seal kit for a DIY job if you're a DIYer, and this could get you out of trouble, else swap the compressor with a new one, or a service exchange unit. It's made by Wabco, by the way, and used on Audis too.

BTW the system maintains vehicle height constantly until it goes into "sleep" mode 30 minutes after you take the ignition key out. Then it will wake up every 24 hours to check, unless, of course, you use the car before then. The compressor, however, is not used, only coming on if the engine is running.

 

as these guys suggest if the compressor is running, then it is weak and cannot keep up with enough pressure, as suggested you can buy new or refurbish it, see my refurbish kit install video showing you the steps how to to give you an idea whats involved:

http://bagpipingandy.com/installation.html

best regards

Andy

 

Thanks for the info, guys. The car was squat again today. Upon starting it gave low ride indicator but then rose to height after a couple minutes with no fault indicators. Went on 20 minute ride and stayed up whole time with no faults.


Do you think that's a compressor problem and that using the repair kit would fit what's happening?

 

I changed my entire air shock set about 4 years ago including the air compressor (before I knew about the replacement conventional normal strut conversions were available), and was good for about 2 years then started have been having intermittent problems again. I have already replaced another one of my front struts under the Arnott's lifetime warranty last year and I am now getting another run of suspension faults coming up again. The car is pending going in for assessment today (if the mechanic is free.... sigh...).

My mechanic says that this is a common problem for all air shock systems and isn't peculiar to the Jag, in our tropical climate.

I would switch to the coilover conversion if I had to do it all again and be free of the air suspension worries. The only thing that keeps me from doing a coilover conversion now is that the car is coming to 9 years and it is due for consideration for scrap or export at 10 years and I haven't decided definitively on whether to keep the car or get rid of it and reinvest in a newer model, although I am leaning towards the latter.

 

I've had that problem a couple of times now, both when the temp was in the single digits. The compressor is about 2 years old and I've replaced the right rear shock. I went out and the car was all the way down. I started it and it came back up. When I stopped at a light a mile up the road I felt the car "fall" again and the "car too low" message came up. After another mile the car was back to the correct height. Coming home that evening I again felt the car "fall." Pulled over, turned it off, restarted, heard the compressor come on, and 30 second later it was ok. I stopped in my driveway to get the mail, and when I turned around from the mailbox the car had fallen again. I pulled into the garage and the next morning it came right up again.

I think something like an o-ring is shrinking and letting the air dump from the system, which is why all four corners are down. I don't get any codes, and once the temp warms up the compressor lifts the car within 30 or 40 seconds, so it's working fine.

 

I would expect the compressor to become warm when it is running. I wonder if it would help to add some winter insulation?

 

If the car keeps sinking down overnight, this tells me there is a leak somewhere. Of course, your compressor may be getting worn out, but I think further investigation is needed. So get those fault codes read now !

 

I agree that getting the fault codes read is the next thing unless I go ahead and do the coil over conversion. It's hard to consider spending money on a system that could have even more problems because of age and mileage soon after this is addressed, so I'm even hesitant to put money into diagnosing what's wrong now.


I'm trying to find out now what my Jag shop would charge to read the fault codes. So, let's say, a compressor rebuild for around $50 DIY would fix this problem--I'd certainly do that. I wouldn't consider it a good investment at this point to replace any of the air struts with more air struts or replace the compressor. For $1,250 DIY with the Strutmasters coils I can bypass the air suspension and not potentially keep sinking money into it. Thoughts?

 

sounds like a leak problem if the car is sinking to the bump stops. If it lifts back up the compressor is working ok for now

best regards

andy

 

My local Jag service department manager told me on the phone today that during the very cold spell about two week ago he had about a dozen cars come in with similar air suspension problems, and that in this cold spell there have been about five more. Since mine is lifting back up he said there may be nothing wrong with any of the parts, just the seals leaking due to the cold. He recommended not driving it during the cold and waiting until it warms up to see if it will work right. He also described how one car's air suspension system seemed to have truly bit the dust, but after a couple days of warming up actually started working again.


That's great to advise letting it sit, but it's my daily driver, and the three additional cars in my household usually are being used by someone else. Through my research so far I'm leaning toward going ahead with the coil strut conversion using Strutmasters. They'll cost me about $200 less than the Arnott, use Eibach springs, and also have a lifetime warranty. Now I have to decide whether to tackle it myself, which it looks as if I can unless I run into too severe corrosion on the bolts that have to be removed. I found a local indy shop that will do the work at $70/hour--just have to get in there with the car so that they can give an estimate that will probably be around 4 hours.


So that's where I'm at right now ... thanks everyone for your helpful advice and ideas.

 

what part of ohio are you in? I can't find a good indy shop in Columbus; but Cleveland has a couple, I've not looked in Cincy.

Mine is doing the same thing; it will pump up if you let it run.
Another trick from another member here is to start it, let it run several minutes until the air pump kicks off (you can hear, it they automatically time out as an overheating safety). Then turn the car off and start it again, the pump will run a 2nd time. Mine will usually lift with the 2nd hit, but I've not tried since it got into the single digits of temp. Somehow I think the pump isn't going to overheat when it's 6*F out .

I'm driving my TDI, which doesn't like to start much in the cold, but they Eibach


I'm slowly writing out a 'air suspension options' super sorta thread, but from my notes, you can also get a $75 off discount from arnott with a jag forums code, it still worked as of a few days ago. From my notes, arnott was then within $68 (you can get the credit for sending your old shocks to them also; they pay shipping).

Yes, Eibachs for stutmasters; unknown springs for Arnott. Both appear to use Bilstein shocks.

 

I'm near Columbus. The Strutmasters customer service gave me a name of a shop that has ordered from them, Evans Auto Repair, 614-297-1259. I hope to make it in there this morning so that they can give me an estimate. But with a labor rate of $70/hour (which is cheap around here) I don't think they'll need more than 4 hours.


Ordering direct from Strutmasters with shipping will come to about $1,237. I found a site that sells the Arnott for cheaper than the Arnott site. At that site I could get the Arnott for about $10 less than the Strutmasters inclusive of shipping. ARNOTT® C-2290 - Jaguar XJ-Type 2004-2009 Coil Spring Conversion Kit


So now I'm not sure which way to go. With price being equal, which is a better product?


Speaking of cost, it's hard for me to accept putting say $300 into the labor because it looks like a fun DIY project that would be very satisfying. But I'd have to use my father-in-law's garage (have to heat with a propane portable heater) and floor jacks--not a good proposition when it's 0 degrees out. And I might run into some too stubborn bolts. If I wait for it to warm up I'll have to work out borrowing other family members' vehicles to get to work (I drive 35 miles each way). So I'm leaning towards biting the bullet and having the shop do the work. Even if I make it through this winter because it's just the extreme cold causing the problem, I don't want to face another winter with the same uncertainties. So probably the sooner to get it done the better.


I see you've found a way to get the shocks inflated by restarting. Mine is inflating them on the first go-round. Probably the Strutmasters could recommend a shop to do your work, especially if you're near a major metro.

 

I've heard mixed reviews on Evans....wait, let me look.
Here's an email my vw mechanic sent to me from another of his customer who has owned a few jags:

"I would have said to Evans Automotive on Morse. I would still recommend them, but shop prices and keep them in line.

I took Christine's SC430 into them for routine maintenance and they quoted $95 to replace the cabin air filter. I bought the filter for $20, opened the glove compartment, unscrewed to screws, slipped out the old filter and skipped in the new one un five minutes. Question if trust.

I have heard good things about a shop on 33 river road just about a mile north if 5th Ave. Good work, honest, affordable, but a little slow. I am going to have some work done there and will let you know."

so just doing the struts they would probably be good; just have their hours figured out beforehand.
If I hadn't rented out my own garage, I'd be up for doing it there!

I'm trying to find more info on all the options too; I'd really like to know actual spring rates and what exact shocks they use.

Strutmasters makes me a bit nervous. There is another thread where they told a forum member their kit would NOT fit on a VDP. Something about not fitting and too much weight. I've got a VDP and it's the same suspension, just more options.

Arnott makes me a bit nervous too. (like their videos just say 'tighten bolt'. I'd never do suspension work without a torque wrench, and loading the suspension if needed).

 

It's actually not Evans Automotive on Morse but Evans Auto Repair on Fourth Street. I took my VDP in there this morning. They looked at the install instructions I'd printed off and put it up on their rack. They looked on line for a little and came back with an estimate of 4 hours labor (about $300 they said). I think that's very fair from what I've read, and they said they would only charge the actual time.


I've decided to go with the Arnotts after all, since their name is much better known and used. Since my car is re-inflating quickly and holding air while driving, and I can hear the compressor shut off after the immediate inflation upon startup, I've decided to ride out the cold weather and do the coil over installation myself in the spring or summer. I don't think the extra drag on the compressor will make it give out before I can swap in the coils and get rid of the air suspension.


BTW, I specifically asked the sales rep from Strutmasters if the coils would would work on the VDP, and he said they make a kit for the VDP. Regarding the Arnott instructional video, I think they're trying to make it look as simple as possible so as to make more sales. I don't really take it as a technical instruction but more like an outline. While my car was up on the rack this morning and the mechanics were back in their office, I looked around pretty well underneath to see the parts on the video that I would be working with, and that actually emboldened me to try doing it myself. I don't mind saving $300 and getting a lot of personal satisfaction.


I'm afraid of running into frozen parts, but that's part of the challenge. Last summer I was changing front disc pads on a 1995 Astro van and broke off a bolt. I ended up having to use a grinder to cut the caliper off in order to get at the bolt since it was so frozen. So there are always ways to get things done, but in a personal garage with limited tools and no unanticipated parts to stick in when one is needed, it makes we leery.


At any rate, that's the plan now. There are two overnights coming up where it's supposed to drop as low as -15 F, so I'll try to "borrow" another family member's car to get to work on that day. How about that--I buy them and maintain them, and then have to borrow them back.

 

I just ordered the Arnott struts from CARiD.com. I live chatted with someone there to ask if they could discount shipping in order to help me make up my mind between ordering from them or Strutmasters. (I preferred the Arnotts to start with....) Here's the final deal, total cost $1,190.83:

Cost of Arnott struts: $1,180.85
Shipping: 45.41
Subtotal $1,226.26
Shipping discount: $ 35.43
Tax: $ 0.00
Grand Total: $1,190.83

I'm happy with that. They should arrive by Friday, and then I'll try to find a nice day to put them in.

 

Having watched the Arnotts conversion video, are you certain this job could be accomplished with the vehicle on jacks?

I don't have access to a lift and would have to use jack stands or similar if I had to do the conversion in my garage, if it was time to convert due to air suspension failure (thank god, not yet !).

Has anyone done the conversion using just jacks and /or jack stands ?

 

My plan is to do it on jack stands this weekend. I don't see anything in the video that can't be done or reached from just a little off the floor.