Hi All,

I'm just about to fit coilovers to my XJR, after having no end of trouble with the air suspension system. All 4 airbags have been replaced with new and I have also refurbished the air compressor with the kit from Bagpiping Andy only last month. After approx 12 months from airbag installation, one of the rears is leaking and the other is very squeaky. The Air Suspension Fault light is a regular visitor to the display. I have read the Forums with interest regarding the replacement of the airbags with coilovers and have purchased a kit from MaxPeedingRods recently. My 2003 XJR is a Japanese import, with a manufacture date of January 2003. My question is; prior to the installation of the coilovers, what precautions do I need to take in terms of removing all potential error codes that may result from this move..? Is it simply a case of unplugging the ASM and removing fuses..? My system does have the CATS. Any advise would be greatly received.

Thanks in advance... Damian

 

Since it's a 2003 you can and could/ should leave everything related installed in the car. Compressor ,nylon hoses, tank and valve solenoid under spare wheel.
if you install coil over from what ever brand . You just need to unplug the Wabco cats system behind rear seat. On early x350 that should be enough. Later modells do need a Fooling device to not end up with air suspension fault on the dash
Undo the airline on each strut and leave the brass fitting on the nylon hose (leave it where it is just put some masking tape around it and secure against body.

 

For some reason, my 2005 XJ8L still needed the CATS fault message dealing with after fitting coilovers. The solution was:
20PCS 1W Metal Film Resistor 1% 1R~1M 15 100 220 470 ohm 15R 100R 220R 470R 1K 100K 510KΩ - AliExpress 502
I just pushed each end of the resister wire into the two females on the ends of the CATS plugs at the airsprings, then shrink-wrapped them?
CATS message, gone.
Might help you if you find the same problem?

 

Thanks for the responses guys.

I did read somewhere that prior to starting the installation the car should have been driven for 15 minutes or so to level, stabilise and record the pressures and positions in the suspension system. Once back at the place of installation disconnect the battery to retain the last known settings. I can't find this information and am relying on memory somewhat as to what was actually stated after reading copious amounts on the subject. I was wondering whether I have this completely wrong or whether this is required.

Sounds like the fuses don't need to be pulled, just the connectors from the ASM.

I will consider your fix regarding the resistors for the CATS system - Thanks EsRay.

​​​​​​​Regards... D

 

I replaced my Cats Suspension on my 05 XJR with a set of used struts from an S-Type. I unplugged the ASN Module from behind the back seat. Lights are out and no regrets. The car sit about 1/2 inch lower than stock which I like.

 

Superb colour... Looks and sits very well...

Mine sits too high at the front which hopefully will be addressed with the coilover kit, and remove all the faults and hassle from the air suspension.



This is the kit I'm installing...

 

yes indeed . Do drive before if possible . In the place yoi'll be working put the tranny in Neutral and parkbrake engine running watch over bonnet. It might regulate height one last time . TRANNY IN P SWITCH OF ENGINE AND BATTERY

 

I may be wrong, but I believe the new height of your car will be decided by the new coilovers? I fitted adjustable BC Racing coilovers to mine and adjusted the ride height to my taste, irrespective of the final settings (before replacement) for the air suspension, which must surely be totally irrelevant?

 

Yep you caught me

 

On my 2005 Jaguar XJ8L, all that was needed was to disconnect the air compressor, unplug the cats module behind the rear seat, and then perform a hard reboot.

 

Hi Rick,
As well as unplugging the ASM, did you unplug any fuses for the air suspension such as; F6 in the engine compartment and F12 & F52 in luggage compartment..? This has also been stated.
Regards... D

 

Hi EsRay,
My thoughts as well, but I'm sure I read this and questioned it at the time. Just wanted some confirmation.
Thanks... D

 

The car is booked in at the garage for the suspension change on Thursday. I'm hopeful that my expectations are realised with the swap and that all the troublesome error codes disappear... I'll keep you posted.

 

The mechanics who installed the Arnott C-2290 coil/spring conversion kit on my 2005 Jaguar XJ8L had opted to physically access the air compressor itself, and then disconnected the electrical terminations to it. Afterwards, they removed the back seat, and unplugged the cats module. In addition, the mechanics had insulated all of the disconnected electrical plugs that went to the air shocks with electrical tape. They then performed a front end alignment (recommended). A hard reboot was the last thing that was done; nothing else was needed.

 

See my comments in today's forum posting...

 

Well the MaxPeedingRods coilovers have been fitted to the 2003 XJR and they are superb. Ironically, on the day it was delivered to the garage, the Air Suspension Fault light was on. Not anymore. With the ASM unplugged and associated fuses removed, no further suspension related warning lights have been active over the last few days of use.

The damper level is on a 24 click adjustment dial. The fronts are currently set at 10 clicks and the rears 6 clicks. This has vastly improved the handling of the car over the air suspension system. When rough terrain was encountered the air suspension would reverberate and handling would be momentarily lost, especially when the driving was more spirited. Now the car feels planted and the ride has not suffered. Initially, when I first drove the car, it was more wafty (and bouncy) than the air suspension. When the adjustment was checked the fronts were set at 4 clicks and the rears at zero, so this was duly changed.

The ride-height of the vehicle was slightly higher than I liked at first, but the settling in period for the coilover suspension kit is approx one week, where up to 12mm of height can be lost. It has already settled by approx 5mm so its looking better day by day.

I'll keep the Forum informed as to the performance and handling of the car over the next few weeks. But for now, I am a very happy banana...

 

Excellent results and glad you are happy. The only thing I would add, as it is unclear what work was actually performed, is keep everything installed in the event you or next owner wants to go back.

If there are air lines or pump inlets exposed, make sure to tape them off so dust, dirt and fluid do not enter the system.

When I did my 2004 conversion, all I did was unplug the module behind the rear seat, taped the hose ends going to the shocks to prevent contamination, and zip tied them secure. Returning to stock remained an easy option.

 

This was how my 2005 Jaguar XJ8L appeared a couple of months or so after the coil/spring conversion in 2014.

 

Hi kg74,
All the air suspension components have been left in-situ, bar the air struts of course. All ends to the electrical plugs have been sealed with insulation tape and all air-hose ends have been taped to prevent debris ingress. An easy swap back should someone need stress in their motoring life...

 

Greetings,which ohm resistor did you use , i put in a 1k ohm resistor in each connection but still have a fault ? Thank you, Ed