Xantia rear suspension problem

citroDane · Post by **citroDane** » 19 Oct 2010, 15:42

Hi guys,

I see to have a suspension problem I cannot easily diagnose, so I would appreciate
any insight.

Just a couple of weeks ago and quite suddenly the rear end suspension’s
chock-absorbing capability dropped to almost none and we’re being tossed
up and down while riding in the car (it kind of feels like if you drive while the height-adjuster
lever is at HIGH / max). And btw, the red hydraulic lamp turns off after starting the engine as it should.

No I’m pretty positive it can’t be general wear on the spheres because a) they are just a
couple of years old (the old ones were older, didn’t have this feel & performed better) and b) this
happened quite abruptly. Could it be the height-adjuster hydraulic unit sitting in the
middle in the back (dunno the exact name for it) or the sphere connected to it? Any ideas to
help me diagnose this are truly appreciated.

Thanks a lot,
Gabriel

Xaccers · Post by **Xaccers** » 19 Oct 2010, 15:52

If it's a non-hydractive, then look at the ride height, if it's higher or lower than it should be then it could be either a seized corrector linkage or the dogbone between the ARB and height corrector.

If it's hydractive, then the centre soft sphere could have blown.
You said spheres were changed 2 years ago, but which ones? Hydractive have 4 at the back, two corner ones used in hard mode, one hydractive used in soft mode, and the rear accumulator (known as the anti-sink sphere).
It could also be that the rear electrovalve isn't working so it's staying in hard mode.
You can check this with the engine off and all doors and boot closed for at least 30 seconds, open a door and you should hear a click from the front and back and a quiet buzz/hum.

citroDane · Post by **citroDane** » 19 Oct 2010, 16:34

Hi Xac,

Pardon my lack of fluency in the Citoroen lingo (or maybe it is general lack of Citroen knowledge)… I thought hydractive signified that the
car does not sink when you turn off the engine. My car doesn’t. But if hydractive implies you can drive in hard or soft mode and need 4 spheres
in the back for it, then I’ve been mistaken. I have only three (and tree in the front too) and no modes to change between. Btw I changed all six
spheres about two years ago with used refilled ones.
I suppose the middle rear sphere on my car still is an anti-sink one, is it? In which case, it could be that it might have blown?
I doubt if my car has an electrovalve as I’ve never heard it click. I guess that only comes with hydractive models?

Cheers,
Gabriel

Post by **Peter.N.** » 19 Oct 2010, 16:39

If the ride height is correct it could be any sphere or even both, they can suddenly fail due to a rupture. With the height at normal (rear suspension arms pretty well parellel to the road) bounce the back and see how much if any movement there is, none and it will likely be one or both corner spheres, if there is a little movement, as Xac says, probably the centre sphere (if you have one).

Peter

Post by **Peter.N.** » 19 Oct 2010, 16:43

Hi Gabriel

Sounds like you car is not hydractive so the problem will be confined to the corner spheres. The anti sink sphere will not make any difference to the ride. Check rear spheres as previous post, you may find that just one side has gone hard, that will be the duff one.

Peter

jgra1 · Post by **jgra1** » 19 Oct 2010, 16:44

hi CitroDane, in answer to your question, although I am not an expert, I think you have a non-hydroactive car, but a car with antisink.. i.e. a 6 sphere car

hope that helps

citroDane · Post by **citroDane** » 19 Oct 2010, 17:59

Thanks guys.

Ok, so it’s not a hydractvie. Good to know.

One additional discovery; I just drove home from work and tried testing the entire
suspension system’s function and it seems I had a misperception about the problem being
limited to the rear end. The front suspension feels pretty hard as well, I am afraid
Peter, I’ll do the test you suggested later tonight. The ride height seems correct (not different
than before). So if I understand you right, any one of the wheel spheres failing could stiffen
the suspension overall?

Cheers,
Gabriel

citroenxm · Post by **citroenxm** » 19 Oct 2010, 19:22

Well, without guessing, being a 99 car its MOST defenatly anti sink, however, anti sink or not, the actuall anti sink sphere will NOT affect ride softness...

Paul

citroDane · Post by **citroDane** » 19 Oct 2010, 20:15

Did the check for movement / travel on all wheels, Peter.

Actually there was decent bounce on the front suspension –both wheels. But rear suspension –left and
right hand side- was totally stiff. I really couldn't push the back of the car down one millimeter and I gave it all I had.

So I guess I’ll replace both rear spheres and see.

Cheers,
Gabriel

Post by **Peter.N.** » 19 Oct 2010, 22:28

Its very unlikely to be anything else Gabriel.

citroDane · Post by **citroDane** » 19 Oct 2010, 23:55

Thanks a lot Peter, et al.

The support in this forum is second to none!

Cheers,
Gabriel