My VSX Xantia still rides worse than a Vauxhall Viva
What are the symptoms of a flat accumulator sphere on a 94 Xantia Vsx (no anti sink and yes it does click about every twenty five seconds!, too often I know, but are there any other suspension symptoms?) I've changed all six of the suspension spheres and the car still rides very hard despite rising and falling in the accepted fashion during citaerobics, I've also used penetrating oil (oo'er) on all pivots and greased it up, should the hydractive button have a dramatic effect?because I can't really tell the difference when mine is on, and finally, if the hydractive 'effect' is jammed on what would actually be jamming (I'll lube the bugger)? or would it be an electronic problem (fuse anywhere folks?).
I've heard that the VSX rides harder than normal Xants, but on engineering terms, without the hydractive button actuated I can't really buy it, as it is only using the same basic hydraulic circuit as a conventional Xantia especially in a straight line when any elements of the anti roll correction are out of play (and wheels 20mm wider just aren't going to make massive differences).
VSX Xantia concrete suspension
Moderator: RichardW
The Hydractive system reverts to hard mode as default within 30 seconds or so - when engine stopped.
Also the hydractive suspension uses different suspension spheres than standard suspension spheres - with a smaller bore for stiffer suspension - to achieve the hard mode.
In soft mode the center sphere is connected - thus providing an extra spring element achieving the softer suspension.
(sounds duff I know - but the extra sphere adds an extra bore for the LHM to reach a spring element - thus the LHM easier/faster flows in/out against the total spring elements connected)
With engine running - suspension in normal height - car parked - the suspension should be in soft mode.
Thus you can test the suspension softness the usual way - pressing down each end of car.
The switcing between soft & hard modes is done electrically by an electrovalve build into the sphere base of the centerspheres. The power feed is a strange hi-frequency alternating voltage from the ECU.
The electrovalve (active in soft mode) simply opens a pressure relief path to reservoir - for an internal valve piston - which then moves and provides a connection path between the suspension & the rear sphere.
The electrovalve itself is very reliable - but of course the coil or the cabling can be defective - keeping the suspension in hard mode.
The ECU decides soft/hard mode from a number of sensors on car including the manual switch - and the decisions is made from a rather complex algorithm - even overriding the manual setting.
The 25 seconds ticking is not exactly fatal to the suspension functions - rather it indicates the main accum sphere is at end of it's service life. Can't see how this would affect the suspension.
A common problem seem to be wrong sphere types - but that would rather give too soft suspension - if standard wheel spheres fitted.
Any chance rear/front axle wheel spheres have been mixed up ?
- as this would be suspective giving too hard suspension.
Also the hydractive suspension uses different suspension spheres than standard suspension spheres - with a smaller bore for stiffer suspension - to achieve the hard mode.
In soft mode the center sphere is connected - thus providing an extra spring element achieving the softer suspension.
(sounds duff I know - but the extra sphere adds an extra bore for the LHM to reach a spring element - thus the LHM easier/faster flows in/out against the total spring elements connected)
With engine running - suspension in normal height - car parked - the suspension should be in soft mode.
Thus you can test the suspension softness the usual way - pressing down each end of car.
The switcing between soft & hard modes is done electrically by an electrovalve build into the sphere base of the centerspheres. The power feed is a strange hi-frequency alternating voltage from the ECU.
The electrovalve (active in soft mode) simply opens a pressure relief path to reservoir - for an internal valve piston - which then moves and provides a connection path between the suspension & the rear sphere.
The electrovalve itself is very reliable - but of course the coil or the cabling can be defective - keeping the suspension in hard mode.
The ECU decides soft/hard mode from a number of sensors on car including the manual switch - and the decisions is made from a rather complex algorithm - even overriding the manual setting.
The 25 seconds ticking is not exactly fatal to the suspension functions - rather it indicates the main accum sphere is at end of it's service life. Can't see how this would affect the suspension.
A common problem seem to be wrong sphere types - but that would rather give too soft suspension - if standard wheel spheres fitted.
Any chance rear/front axle wheel spheres have been mixed up ?
- as this would be suspective giving too hard suspension.
Thanks Anders, though that rather puts paid to my plan of diconnecting the hydractive wires from the solenoid / valve assy in order to see if it was jamming on (rather that would make it jam on I presume?), whereabouts is it, you are describing it as being on the centre sphere that is utilised to soften the suspension, I am only aware (though I haven't been under the car yet, I have only had it three weeks)of 7 spheres, one basically in each corner, one under the o/s headlamp (ft suspension) one under the rear axle beam (rr suspension) and the accumulator at the front of the engine, the four outers have been changed in october and I had the front and rear ones done by a Citroen specialist (Buzz Arnold in Shedfield, 23yrs Citroen only, so I hope he didn't mix em up!)don't tell me I have missed the only one that is likely to work off the hydractive button (I bet I bloody have haven't I!)
Cheers mate
Dom.
Cheers mate
Dom.
Well Dom -
The 4 wheel spheres are pretty obvious in terms of function & location - no mystery here.
So are the main accumulator fitted ON engine.
That makes 5 spheres.
The remaining 2 spheres are the HA center spheres - 1 for each axle - located on car near the relevant axle - exactly as you found the odd extra rear sphere and the o/s headlamp located extra front sphere.
The term "center" sphere is not to be taken literally - as there is no mechanical needs to locate it exactly at center to the relevant axle. They are connected by (10mm) hydraulic steel pipes - as the function relies only on hydraulics.
The base at which these 2 HA center spheres are fitted on - should have an electric cable fitted for the HA electrovalve - as simple as that. The cable is most likely hidden/run in a protective (plastic) tubing/sleeving - not exactly looking like a cable. But clearly not a hydraulic related/looking item.
It's important you know that if these 2 "center" (HA) spheres (or either) are(is) flat - it means you have no extra suspension element connected in soft mode - as a flat sphere can not provide any spring action.
This can give the impression that you can not get the car to switch to soft mode.
As you have service history on the 6 wheel and center spheres - it would be nice to know if these spheres was replaced with NEW units - or they have been regassed - or replaced with recon units.
It's known that regassed or recon units are quite UN-reliable - meaning they can loose their pressure again rather soon.
If you're the type of patient home-fiddler - then it's in fact possible to test a sphere on the car :
As you know - a (nearly) flat main accumulator sphere is indicated by rather fast ticking interval from the regulator.
(in your case approx 25 seconds)
A flat sphere would cause rapid ticking.
A good (new) main accumulator sphere should give a ticking interval of some 1-2 minutes - maybe even more.
Please note the ticking interval depends on the sphere gas pressure - thus a wheel or HA sphere with (normal !) lower pressure will give faster ticking interval - than a new main accumulator.
On www.gsfcarparts.com - you find a (download) table for sphere types & pressures.
If you then swap a suspect sphere with the main accumulator sphere - then you can deduce - from the ticking interval - in what approx condition a suspect sphere is.
This is because any sphere can in fact be used as a main accumulator sphere - at least for testing.
But <font color="red"><i>NEVER</i></font id="red"> the opposite - i.e. a main accumulator should not be used as a wheel sphere while driving the car.
The 4 wheel spheres are pretty obvious in terms of function & location - no mystery here.
So are the main accumulator fitted ON engine.
That makes 5 spheres.
The remaining 2 spheres are the HA center spheres - 1 for each axle - located on car near the relevant axle - exactly as you found the odd extra rear sphere and the o/s headlamp located extra front sphere.
The term "center" sphere is not to be taken literally - as there is no mechanical needs to locate it exactly at center to the relevant axle. They are connected by (10mm) hydraulic steel pipes - as the function relies only on hydraulics.
The base at which these 2 HA center spheres are fitted on - should have an electric cable fitted for the HA electrovalve - as simple as that. The cable is most likely hidden/run in a protective (plastic) tubing/sleeving - not exactly looking like a cable. But clearly not a hydraulic related/looking item.
It's important you know that if these 2 "center" (HA) spheres (or either) are(is) flat - it means you have no extra suspension element connected in soft mode - as a flat sphere can not provide any spring action.
This can give the impression that you can not get the car to switch to soft mode.
As you have service history on the 6 wheel and center spheres - it would be nice to know if these spheres was replaced with NEW units - or they have been regassed - or replaced with recon units.
It's known that regassed or recon units are quite UN-reliable - meaning they can loose their pressure again rather soon.
If you're the type of patient home-fiddler - then it's in fact possible to test a sphere on the car :
As you know - a (nearly) flat main accumulator sphere is indicated by rather fast ticking interval from the regulator.
(in your case approx 25 seconds)
A flat sphere would cause rapid ticking.
A good (new) main accumulator sphere should give a ticking interval of some 1-2 minutes - maybe even more.
Please note the ticking interval depends on the sphere gas pressure - thus a wheel or HA sphere with (normal !) lower pressure will give faster ticking interval - than a new main accumulator.
On www.gsfcarparts.com - you find a (download) table for sphere types & pressures.
If you then swap a suspect sphere with the main accumulator sphere - then you can deduce - from the ticking interval - in what approx condition a suspect sphere is.
This is because any sphere can in fact be used as a main accumulator sphere - at least for testing.
But <font color="red"><i>NEVER</i></font id="red"> the opposite - i.e. a main accumulator should not be used as a wheel sphere while driving the car.