I ran over a speed bump and hit the underside of my XJ8 fairly hard. Now my suspension seems frozen and immovable. Is it possible I have pinched the air suspension pipe and can I replace this pipe?

 

Not likely on the pinched air pipe. Also, there ar a number of pipes in the system that are distributed from the air compressor to a reserve tank to a distribution block, then to the corners. But, yes, if a run was damaged, it can be replaced.

Please describe more, the symptoms of "frozen and immovable". What are the circumstances that lead you to conclude that?

 

The symptoms of my suspension problem is that the car rides like an old 'buckboard' with no suspension travel at all. When I get out of the car and press down on any of the corners to check the suspension, the car has no travel at all and feels rock hard...as if there are no springs at all.
Is the car in 'transportation mode'?
Thanks for your help.

 

It might be acting like it is in transportation mode (and by your description); however, the ASM cannot enter into transportation mode w/o the intervention of a WDS. Also, in transportation mode, the air suspension fault message is constantly displayed.

Very interesting problem, I could offer a lot of suppositions, but I'm guessing w/o actually seeing the car. Might even be guessing then.

The hit on the speed bump should have triggered an ASM response individually, by axle (front/back) Even if it hit extremely hard and bottomed out the air springs, one axle at a time, the ASM shouldn't continually respond with an overfilled condition at all four corners.

I'll noodle on it some more...

 

Thanks Steve,
My Jaguar is in the service dept now. They tell me that it needs a new speed direction sensor in the steering column. It should be fixed today for $275.
Last week I sprayed some WD40 down the steering column to quieten the squeeky steering...it looks like I might have caused the problem. I never realised there are sensors there. That was an hour before I hit the speed bump hard.
I have since found out on this forum about the additive for the noisy steering.
Thanks again for your help and I promise to be more careful with my WD40 can in the future,

 

Ah! Thanks for the update, and goes to show how difficult these problems are to diagnose online. Would never have gone there because I was unaware of your actions with the WD40.

The sensor in the steering is actually a Yaw sensor that measures and sends signals to the ASM as to the severity of a turn of the wheel, or a "swerve". Input from this sensor activates a "fast cycle" action by the ASM to counteract body roll. And, it is a speed sensor, in effect, as its variable voltage signal increases/decreases in voltage at a speed related to the driver's actions.

Thanks again, you're were probably more help to me than I was to you!

Best,

 

Thanks again Steve for your input.
My Jag is now fixed and it only cost $275 so I think I got off lightly.
What a wonderful car the XJ8 is when running nicely.
Best regards

Joe