Hello
I recently bought a meticulously cared for 2004 xj8 with 120,000 miles. It has sat for much of the last 3-4 years in a garage as the previous owner bought a new model. I was skeptical to buy this car as I know they can be expensive to repair.
The day after I bought it, I got the suspension to low, air system ride system problem warning lights and the low rider front end. It has been very cold in PA, and after I drove the car a few miles and restarted it, it did pump up and work fine. Now the compressor does turn on and I can hear the air coming out of the top of the passenger side front strut. The air line is not leaking, so I assume that the bag has a hole at the top of the strut and the air is escaping that way. I am going to heat up my garage to see what happens, but this sounds like a classic example of a bad strut. Is there anything else it could be or other way to verify?
Thanks
Paul

 

Sounds like you and your Jaguar are spending some quality time together soon.
Fronts from Arnott work, as well as R M T, to rebuild yours, trade yours in, or buy another rebuilt shock.
Coil over conversion is an option as well.
Like the air shock set up myself.
Both Arnott, & R M T, work well so far in my experience.

 

Thank you for the reply. The replacement labor does not look that bad, as i am a decent backyard mechanic. I was hoping to get the reply," there is a check valve the sometimes sticks" or something like that, but it sounds like I have to replace the shock. I will remove and inspect to be sure it is bad.....

 

Lower bolt is the only fly in the ointment, if like my 07's were.
The the 04's came loose, car from the Carolina's.
The 07, had spent half its life in the Ohio salt belt.
Spray it down with oil and hope they come loose.
Otherwise it's way more work, but still a doable job.

 

Hi Paul,

Your symptoms are consistent with a leaking top seal in the front right air spring/shock absorber unit. Top seal leaks tend to worsen in cold weather, and frequently do not leak much if at all in warm weather. So far, we do not know of an easy way to repair the top seal, since the part is not available from Bilstein and the unit is crimped together and not readily disassembled.

If you're willing to pay for them, the best option in my opinion is to purchase two new Bilstein B4 air spring/shock absorbers, replace both of your fronts, and save the one non-leaking unit as a spare. The Bilsteins have the adaptive damping solenoids that will retain your ECATS functionality. As far as I know, none of the aftermarket units will preserve your ECATS functionality. Rock Auto carries the Bilsteins currently priced at $675.79. I recently put a pair on an '04 and the ride and handling were superb.

It is also likely that the piston ring/seal in your air compressor is worn and needs to be replaced. This is a relatively easy DIY job with an inexpensive kit available from our member Andy at bagpipingandy.com.

For more information on the air suspension and ECATS, see the following post:

Air Suspension & ECATS System Summary: Components & Operation

Please keep us informed.

Cheers,

Don

 

thank you for the reply and the link. Interesting that people even try epoxy sealant to try and stop the leak - not sure how that could work.
What happens if I go with an aftermarket unit that does not have the ECATS connector or compatibility? Will I get error messages as well as poor performance?
Paul

 

The post I linked you to explains how ECATS works - with aftermarket air springs/shocks or coil-over shocks the ECATS adaptive damping functions are lost. To some owners it's no big deal. Others don't want to lose the anti-dive, anti-squat, improved cornerning, etc. Some of the vendors who sell aftermarket units include an electronic device to fool the Air Suspension Control Module (ASM) so it will not trigger ECATS faults, some vendors do not. For example, Arnott Industries calls theirs an Electronic Bypass Module (EBM), Strutmasters calls theirs a "Module to Remove Suspension Warning Light."

By the way, I am fairly confident that some type of sealant or epoxy could be used to at least reduce the effects of a top seal leak, but have not yet had time to experiment to determine the best product and application technique. My thought is that with the right sealant that could flow at temps below 40F, you could apply a slight vacuum to the air bladder so that the sealant/epoxy would be drawn into the leaking void, improving the seal. You could then fill most of the recess around the ECATS solenoid as long as you put a tube or some other "dam" around the solenoid to prevent sealing it in or contaminating its electrical contacts. But you'd still have shock absorbers that have done 120,000 miles...

Cheers,

Don

 

Well, it has been very cold in the NE US (1F) and when I looked at it again to do the soapy water test, both front struts are now leaking! I am going to try an epoxy patch first, but get the feeling I will be buying the remanufactured units off EBAY for $220 each. If I took this car to the dealer or even a Chain type garage, I would end up spending more for the shock replacements han I did for the entire beautiful car!

 

Thats why you can buy them for so little cash.
The cost to fix the suspension alone chases a lot of people away.
Fix them yourself for about the same as any other car.

 

I would just opt to get some remanufactured OEM units.

RMT sells rebuilt oem struts for less than half the cost of new ones. If you are on a budget, I would go this route. Always replace the struts in pairs too (Front set / Rear set)

I would also rebuild your air compressor, as its likely been well worn from constantly running trying to pump up a leaky system. Scoop the kit from Bagpipingandy.

 

Sent my old ones off of the 04 into R M T to be rebuilt..
Then put them on the 07 for $550, including shipping both ways.
The NEW Arnotts on the 04, cost me $830.
So the R M T's rebuilding mine, were a lot less.
That makes the idea of buying used shocks off the internet, questionable to me.
Best way to make GOOD use of your used shocks.
Send them to R M T, I M H O.

 

ebay air shock $250.00each

 

If R M T still have the same deal going on at $550 for your two front core, rebuild's.
At $275 each, with some kind of warranty, (not needed) may be a better bang for the buck.
Am very pleased with the new Arnotts i put on the 04, as well.
But they were $415 X 2 = $830 delivered.
Good luck with your choice

 

Kudos to Don B remarks
" It is also likely that the piston ring/seal in your air compressor is worn and needs to be replaced. This is a relatively easy DIY job with an inexpensive kit available from our member Andy at bagpipingandy.com."

Andy at bagpipingandy.com website... $41 approx
sells custom-created rebuild parts for arnott air suspension compressors
Very important..relatively easy rebuild... as compared to removal & reinstall of air struts.
Critically important to do this ... as computer runs air compressor continually oftentimes when one has a leaky air suspension problem.
Thus.... causing pump piston seal to work more than mileage would indicate.
Little $$$ money for parts...
great need for function and "peace of mind"

Los Angeles CA