Hello,

I am sorting a few issues in my 2012 XJ air suspension. It appears the exhaust valve has shorted, as it is hot, and does not change state (click, or open) even though it is being supplied with battery voltage. I am trying to diagnose this, as my rear suspension is not leveling, and is about 2" higher than normal. At one time I had a diagram of the air suspension system, which would be beneficial in troubleshooting, but I cannot find it anywhere. Does anyone have a source for one? It is not in the service manual, that I can find. Does anyone have one to share?

Thanks,

John

 

First post in this section of the forum but have had couple thousand in the XK area.
Moved on to the big boy cars with a week ago purchase of a 2019 XJ L 5.0 Supercharged.
Looked at a low mileage one that had a bad wheel/suspension issue. Above 50 mph it felt that it had a tread separation issue. Didn't really feel like it was speed sensitive. Reviewing the factory warranty efforts there were a couple alignments, balance efforts and finally a full 4 tire replacement at 35k miles. Passed on that one as the dealer didn't seem inclined to provide any reasonable resolution and it was a few months out of warranty.
After further exploration, found a car within its factory warranty. Bought it from Florida dealer that assured me that there were no problems with the car. (HA)
This car has exactly the same issue, but at a much lower level. Wheel 'hop' begins at about 50mph on smooth asphalt. Again, doesn't feel speed sensitive. Doesn't get worst at higher speeds. Again the factory warranty history displays multiple efforts of balance and alignment and finally full 4 tire replacement at 32k miles.

I have an appointment with the closest Jaguar dealer Wednesday..

Is this a chronic suspension issue? Search of forum did not identify a closer thread subject that I found.

My first guess is electronically controlled suspension system is pulsing air shocks above 50 mph.

Other opinions before meeting with Jaguar service would be appreciated.

 

The best of the best!
What tires are on there?
And you're feeling it while driving a steady speed, not just while braking?
It should help that it's not speed-specific, so as you've stated, not a balance problem.
I would say that a bent rim might cause it, but you would feel a difference at different speeds with anything to do with the wheel.
Have you tried pulling the connectors from the tops of the 2 front shocks to see if there's a noticeable difference in the ride? That's easily done.
A more common problem is steering wheel shake when braking & coming to a stop, but sounds totally different from what you're experiencing.