Xantia Hydractive 'bypass'???

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
citroenesque
(Donor 2016)
Posts: 400
Joined: 28 Feb 2008, 19:16
Location: Essex
My Cars:
x 4

Xantia Hydractive 'bypass'???

Post by citroenesque »

I am still having a few issues with the rear suspension on the Xantia. It is not good at absorbing bumps and it's slow to react over uneven surfaces. It generally feels like the spheres have gone hard. I am yet to Hydraflush the system although it is new LHM in there - and the filters were given a clean although they weren't overly dirty. OK, I hear you say, do that and get back to us... well I will, but I was chatting to a couple of experienced Citroen/Xantia owning chaps at the East Midland's group meet a week ago and the suggestion was made that, because the hydractive 2 system is pants (it's the gist of what was said) the following should be considered:

Fit a flat centre sphere and fit 'normal' non-hydractive spheres to the rear; this will give a much better ride and by-pass the issue I appear to be having.

Can it be that simple??? In which case, why not fit non-Hydractive spheres to the front and keep the suspension in 'Sport' mode all the time, negating the need to replace centre spheres with flat ones? (Or is that too daft for words?)

The other thing observed was that it points to an electrovalve problem (well it's the only bit that hasn't been replaced back there)... but how likely would that be?


As I understand it, rear non-Hydractive spheres are 400cm3, 30bar with a 1.0mm bypass valve (as opposed to 0.5mm for H2 spheres) and similarly on the front non-H2 are 55bar and 1.5mm (as opposed to 50bar and 0.6mm). This would seem to make a noticeable difference?
Last edited by citroenesque on 31 Oct 2011, 12:37, edited 1 time in total.
1992 Citroen BX TZD Turbo Diesel hatch, white, 92k
*SOLD* 1998 Citroen Xantia Ser.1 Turbo Diesel manual, Desire Limited Edition hatch, Mauritius Blue, 118k
2003 Rover 75 CDTi Connoisseur SE Tourer auto, BRG, 135k
User avatar
DickieG
Monaco's youngest playboy
Posts: 4877
Joined: 25 Nov 2006, 09:15
Location: Buckinghamshire
My Cars:
x 38

Re: Xantia Hydractive 'bypass'???

Post by DickieG »

The suggestions given should work OK, I can't see any reason why not but before you go that route is the Hydractive system buzzing and clicking appropriately as in buzzing for 30 seconds after opening a door followed by a click when the door followed by the valves shut? Has a Lexia session been tried on the ECU?

The difference in firmness between Hydractive and non Hydractive sphere's is quite noticeable.
13 Ram 1500 Hemi
14 BMW 535D Tourer
19 BMW i3s
06 C3 Desire 1.4
72 DS 21 EFi Pallas BVH
citroenesque
(Donor 2016)
Posts: 400
Joined: 28 Feb 2008, 19:16
Location: Essex
My Cars:
x 4

Re: Xantia Hydractive 'bypass'???

Post by citroenesque »

Hi, Jim carried out the Lexia session, once when I got the car and again at the CXM Xantia Rally. It buzzes and clicks appropriately but I will double check this pm, (and firms up a short time after using the car too).
1992 Citroen BX TZD Turbo Diesel hatch, white, 92k
*SOLD* 1998 Citroen Xantia Ser.1 Turbo Diesel manual, Desire Limited Edition hatch, Mauritius Blue, 118k
2003 Rover 75 CDTi Connoisseur SE Tourer auto, BRG, 135k
citronut
Posts: 10937
Joined: 29 Apr 2005, 00:46
Location: United Kingdom east sussex
My Cars:
x 92

Re: Xantia Hydractive 'bypass'???

Post by citronut »

are you sure the hight corrector linkage's/turrets are floppy free and not seized up,


regards malcolm
citroenesque
(Donor 2016)
Posts: 400
Joined: 28 Feb 2008, 19:16
Location: Essex
My Cars:
x 4

Re: Xantia Hydractive 'bypass'???

Post by citroenesque »

New linkage and height corrector fitted - and moves freely!
1992 Citroen BX TZD Turbo Diesel hatch, white, 92k
*SOLD* 1998 Citroen Xantia Ser.1 Turbo Diesel manual, Desire Limited Edition hatch, Mauritius Blue, 118k
2003 Rover 75 CDTi Connoisseur SE Tourer auto, BRG, 135k
Citroenmad
Posts: 8125
Joined: 04 Dec 2008, 22:08
Location: Northeast
My Cars: 07 Citroen C6 V6 HDi Exclusive - Red
07 Citroen C5 HDi VTR - Red
09 Citroen C3 1.4i VTR - Silver
01 Citroen Saxo 1.1i Forte - Mango Orange
93 Ford Mondeo 2.0i GLX
19 Hyundai i10
x 110

Re: Xantia Hydractive 'bypass'???

Post by Citroenmad »

You could always try an ecrofting diode kit and see how that goes?
I suppose the spheres are as they should be? It's not unknown for cheapies to pop the diaphragm, not in my experience anyway.
Chris
07 Citroen C6 V6 HDi Exclusive - Red
07 Citroen C5 HDi VTR - Red
09 Citroen C3 1.4i VTR - Silver
01 Citroen Saxo 1.1i Forte - Mango Orange
.
93 Ford Mondeo 2.0i GLX
19 Hyundai i10
Peter.N.
Moderating Team
Posts: 11563
Joined: 02 Apr 2005, 16:11
Location: Charmouth,Dorset
My Cars: Currently:

C5 X7 VTR + Satnav Hdi estate Silver
C5 X7 VTR + Hdi Estate 2008 Red

In the past: 3, CX td Safaris and about 7, XM td estates. Lovely cars.
x 1199

Re: Xantia Hydractive 'bypass'???

Post by Peter.N. »

I would be inclined to fit non hydractive spheres and leave everything else alone, you shuld get a very nice soft ride when all is working.

Peter
citroenesque
(Donor 2016)
Posts: 400
Joined: 28 Feb 2008, 19:16
Location: Essex
My Cars:
x 4

Re: Xantia Hydractive 'bypass'???

Post by citroenesque »

Such a diode kit was kindly fitted by Jim at the rally, and all spheres regassed in the summer....

Peter; So all I need to do is swap out the hydractive spheres on the rear (or would I need to do all four corners?), replacing them with the non-hydractive ones and leave the centre sphere(s) alone then?

Sounds an easily rectifiable experiment if nothing else I guess :)

Another thing (although I doubt this has any real bearing) is the anti-sink works fine, but on starting there's really quite a pronounced *drop* as that disengages and the system is still pressurising (takes a bit too long for my liking but I can forgive it that).
1992 Citroen BX TZD Turbo Diesel hatch, white, 92k
*SOLD* 1998 Citroen Xantia Ser.1 Turbo Diesel manual, Desire Limited Edition hatch, Mauritius Blue, 118k
2003 Rover 75 CDTi Connoisseur SE Tourer auto, BRG, 135k
User avatar
Xaccers
Posts: 7654
Joined: 07 Feb 2007, 23:46
Location: Milling around Milton Keynes
My Cars:
x 184

Re: Xantia Hydractive 'bypass'???

Post by Xaccers »

A sink at start up is normally caused by spheres being low.
The anti-sink valve is kept closed by the sphere side pressure being higher than the (not turning) pump side pressure.
If the spheres are low then before the pump side gets to "lift up" pressure, it is able to overcome the sphere side pressure and the anti sink valves open causing the car to sink at first.
I'd want to get the spheres checked to confirm they're OK, if they've been regassed then it could be the diaphram has ruptured since it was done.
1.9TD+ SX Xantia Estate (Cassy) running on 100% veg
1.9TD SX Xantia Hatchback (Jenny) running on 100% veg for sale
Laguna II 2.0dCi Privilege (Monty)

DIY sphere tool
citroenesque
(Donor 2016)
Posts: 400
Joined: 28 Feb 2008, 19:16
Location: Essex
My Cars:
x 4

Re: Xantia Hydractive 'bypass'???

Post by citroenesque »

Will do, Xac. There's no guarantee, as you say, that that aren't fubar. If it transpires that they are OK, I think non-hydractives need to go on and see what happens! :) And if one of more have failed, I might still do that.
1992 Citroen BX TZD Turbo Diesel hatch, white, 92k
*SOLD* 1998 Citroen Xantia Ser.1 Turbo Diesel manual, Desire Limited Edition hatch, Mauritius Blue, 118k
2003 Rover 75 CDTi Connoisseur SE Tourer auto, BRG, 135k
User avatar
CitroJim
A very naughty boy
Posts: 49534
Joined: 30 Apr 2005, 23:33
Location: Paggers
My Cars: Bluebell the AX, Polly the C3 Picasso, Pix the Nissan Pixo, Propel the duathlon bike, TCR Pro the road bike and Fuji the TT bike...
x 6163
Contact:

Re: Xantia Hydractive 'bypass'???

Post by CitroJim »

Whoever said hydractive is 'pants' is really talking a load of pure, unmitigated spheres. When working properly it is excellent but it does require a lot to be working properly. Sphere condition (all of them) and spec. is critical and also it is critical that the pressure regulator is putting out the correct pressure. The hydractive electrovalves operate both on pressure and an electrical signal. The electrical signal helps them operate but their main operating force is hydraulic pressure and if the pressure regulator is low on output then this will cause it.

Another cause is the electrovalve itself. If leaky internally then it will give the symptoms you have.

Also, the 'going hard' my be caused by the anti-sink valve operating when it shouldn't, again due to low main-line hydraulic pressure for whatever reason and again, often due to a leaky electrovalve.

It's quite Ok to use non-hydractive corners but you must force hard mode and blankers on the centre spheres is one way to do this very effectively but in my experience it's still not quite as soft and good as a proper non-hydractive set-up. There is an easier way to force permanant hard mode - see later!

One thing you must not do is use non-hydractive spheres and allow soft mode as well, especially at the front. The car will handle like a bowl of jelly. I know as Rattiva II has an ongoing problem where she's stuck in soft at the front. Due to not having any I popped on a pair of non-hydractive corners and it was terrible. You'd think it would be lovely and soft and squidgy but damping was all wrong and the overall effect was nasty. I now have peroper hydractive corners and things are much better but it's still clear that by not switching hard when it should the front end is still a bit wrong.

Permanent hard mode for use with with non-hydractive spheres can easily be realised by removing Fuse F8 (20A) from the engine bay fuse box to power down the hydractive ECU. Then the electrovalves will never operate and this will give permanent hard mode...

A good test for leaky electrovalves is to force permanent hard mode by lifting F8 and measuring your tick rate. The re-eanble soft mode and measure the tick rate again. Any significant difference in soft mode, say a much shorter tick interval, indicates one or the other of the electrovalves is leaky when in soft mode.

Only remove and replace F8 with the engine stopped and ignition off. If in soft mode, await the switch to hard mode before pulling the fuse.
Jim

Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...
robert_e_smart
Posts: 1031
Joined: 23 Oct 2009, 10:51
Location: Northern Ireland
My Cars:
x 14

Re: Xantia Hydractive 'bypass'???

Post by robert_e_smart »

Hydractive is a waste of time!

Phil, have a read at this thread http://www.club-xm.co.uk/forum/viewtopic.php?f=7&t=1794" onclick="window.open(this.href);return false;. I have done this to 2 cars, and about to do it to another. Why does an Automatic Xantia need sports suspension, it just doesn't make sense to me.

Also bear in mind that the BX is a lot softer than the Xantia and Xm!
1990 XM 2.1 Turbo SD
1991 BX 16 TGS Auto
1992 ZX 1.6 Aura Auto
1994 Xantia 2.0 16V VSX
2008 C5 2.7 Exclusive
User avatar
Xaccers
Posts: 7654
Joined: 07 Feb 2007, 23:46
Location: Milling around Milton Keynes
My Cars:
x 184

Re: Xantia Hydractive 'bypass'???

Post by Xaccers »

robert_e_smart wrote:Hydractive is a waste of time!
:roll: ;)
1.9TD+ SX Xantia Estate (Cassy) running on 100% veg
1.9TD SX Xantia Hatchback (Jenny) running on 100% veg for sale
Laguna II 2.0dCi Privilege (Monty)

DIY sphere tool
User avatar
DickieG
Monaco's youngest playboy
Posts: 4877
Joined: 25 Nov 2006, 09:15
Location: Buckinghamshire
My Cars:
x 38

Re: Xantia Hydractive 'bypass'???

Post by DickieG »

robert_e_smart wrote:Why does an Automatic Xantia need sports suspension, it just doesn't make sense to me.
To allow it a softer ride yet still have better control over body movement, Hydractive addresses one problem with standard Hydropneumatic suspension in that it smooths out the minor corrugations that standard Hydrpneumatic suspension transmits into the car body.

Why do you think that an automatic has less need for Hydractive over and above say a TD? Other than a few supercars just about all of the most powerful cars use an automatic gearbox :?
13 Ram 1500 Hemi
14 BMW 535D Tourer
19 BMW i3s
06 C3 Desire 1.4
72 DS 21 EFi Pallas BVH
User avatar
CitroJim
A very naughty boy
Posts: 49534
Joined: 30 Apr 2005, 23:33
Location: Paggers
My Cars: Bluebell the AX, Polly the C3 Picasso, Pix the Nissan Pixo, Propel the duathlon bike, TCR Pro the road bike and Fuji the TT bike...
x 6163
Contact:

Re: Xantia Hydractive 'bypass'???

Post by CitroJim »

robert_e_smart wrote:Hydractive is a waste of time!
Spheres! Total and utter spheres!

Drive a non-hydractive and hydractive Xantia back-to-back and feel the difference. then drive a hydractive Xantia stuck in soft mode and you'll see :wink:

When you have faults on the hydractive system or the spheres are wrong it comes home just how finely tuned the suspension systems are and how little it takes to upset that fine turning...

I'd never recommend forcing soft mode on a hydractive Xantia as you do on the XM Robert but perhaps it works better on the XM and brings about a positive result but it sure does not on a Xantia.

As I sad earlier, fitting non-hydractive corners and forcing permanent hard mode is not entirely satisfactory either. It's that fine turning again.
Jim

Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...
Post Reply