Xantia rear suspension

[Chetiya Dias]

Hi Everyone. wish all a Merry Christmas. I have a problem with my non active Xantia. Sometimes when I start the car as the stop light goes out the back goes down and comes up instantly. Any ideas.

Regards Chetiya

[dei9]

Hi,

What year is your Xantia? And by non active I assume you mean it's not working as it should (not it's not an Activa?)

Firstly, is the height control lever at the right position, and the lever's handle full settled and sprung back up in the lock position, the one one notch back from the lowest setting (lowest being closest the radio).
Check the fluid level in the LHM resevoir, put the car on it's highest setting, (furtherst from the radio), pop open the bonnet and make sure the orange disk is between the two gold lines in the window on top of the resevoir, it's the big black thing on the passenger side near the windscreen with lots of pipes going out of the centre thing.

Failing that, we need more detail on the symtpoms: Does it go down low and then back up to normal? Or does it sink down a bit and then settle too high? Normal height is three fingers between the top tyre and wheel arches? (but I like it to be a squeeze, i.e 2.5 of my fingers)

Failing that: It sounds like a sticky height corrector. Maybe do some 'citrobeotics' with it, i.e move that height control lever to high, then wait a bit, then all the way to low, then wait a bit, then back to high, then back to low, do this a few times, giving it a few minutes to settle on each setting (budget a good half an hour of your time to complete this). Do that, then get back to us with how it settles when you put it back onto the normal position (the 3rd one from the back, or one back from the lowest).

Good luck.

[citroenxm]

Its NOT a sticky height corrector because the car comes back up...

Its a failing anti sink system AFTER the anti sink valve., the anti sink works because the car stays up. But as the remaining system after the anti sink valve is low on pressure after the car has been parked for a while, the rear anti sink valve opens when the car is started and operating pressure is reached but the rear drops as the "Held Pressure" in the rear returns into the rest of the system that lost the pressure. In other words reserved pressure is not being kept in the system.

The Rear Centre Brake sphere - also incorrectly called an Anti sink Sphere is possibly dead, also the front Accumilator sphere..

Its not REALLY a massive problem and one of mine did it for years, and never gave me any issues...

[sparksie]

Mine has been doing that ever since I got it.
I didn't know it shouldn't!
Pretty sure it's not the front accumulator sphere, because the brakes work, even before the STOP light goes out.
I've played with it and found the brakes still work after a period of several days of non running, which I'm pretty sure they wouldn't if the accumulator sphere wasn't holding pressure.
Now the rear one is interesting. I don't yet fully understand the functions of the various spheres, so that may be a candidate.
I won't be playing with it for a while, though. I'm in the habit of starting the car, waiting for the STOP light to go out, the rear to "slam", rise and settle, then driving off. The only potential problems with this are the risk to anything hiding under the car and the need to avoid parking over anything that might not fit underneath the bottomed out rear end.
One thing I have noticed, that the OP hasn't mentioned...
If I don't alter the loading on the car after switching off, the suspension will usually stay up after a restart.
If I change anything (climb in/out, put a tool box in the boot, etc), then it WILL drop, regardless of how long it's been parked.
Does this throw any light on the matter, or is it a red herring?

[Chetiya Dias]

Thanks everyone. Its a 2000 Xantia 2 with 2.0i 16v engine. I put the car on highest and lowest positions several times and so far so good. Sometimes the duration for pressurization varies from time to time. the time the stop light to go of keeps on increasing and when I check the front regulator ticks its below 20sec. After that when I put the car to highest and lowest positions several times and back to normal height the ticking gap increases over 30sec. sometimes over 1mnt. Then even after I start after 2-3 hours stop light offs quickly. Then again after I drive the car the time the stop light to go off increases.

[Chetiya Dias]

Hi. I bleed the system including brakes and everything seems to be working fine. Ticking over 40sec and started the car after couple of hours and stop light offs instantly. But moment I press the brake pedal everything changes. Ticking below 20sec and stop light takes long time to go off. What can be the cause guy's.

[Chetiya Dias]

Hi. Can anyone please help me with my problem.
Regards Chetiya

[myglaren]

Looks like a failing accumulator to me.

[Chetiya Dias]

You mean the accumulator or the sphere

[myglaren]

The accumulator is the sphere.

[Chetiya Dias]

But I replaced all six spheres and done only 6000kms

[myglaren]

As long as you haven't been sold a dud then it won't be that then.

Have you taken note of Paul's suggestions in this post above:

Its NOT a sticky height corrector because the car comes back up...

Its a failing anti sink system AFTER the anti sink valve., the anti sink works because the car stays up. But as the remaining system after the anti sink valve is low on pressure after the car has been parked for a while, the rear anti sink valve opens when the car is started and operating pressure is reached but the rear drops as the "Held Pressure" in the rear returns into the rest of the system that lost the pressure. In other words reserved pressure is not being kept in the system.

The Rear Centre Brake sphere - also incorrectly called an Anti sink Sphere is possibly dead, also the front Accumilator sphere..

Its not REALLY a massive problem and one of mine did it for years, and never gave me any issues...

regarding the leaking electrovalve.

[Chetiya Dias]

I replaced a second hand rear anti sink valve as well. Still the same. Then may be the rear center sphere is gone. Paul and Steve can this be the reason for the stop light taking a longer time to off and also the low regulator ticks.

[myglaren]

There are others far more knowledgable than I and Paul is one of them. It is about fifteen years since I ran a Xantia so am out of touch but from your symptoms the accumulator was the first suspect and then as Paul pointed out, a leaking electrovalve.
If you are happy that both these are OK then I think that either there is a substantial leak somewhere or the HP pump or regulator is at fault. Either the pump not supplying sufficient volume or the regulator cutting out too soon.

Personally I would check the returns to the LHM reservoir to see if there is a component returning excessive amounts indicating a defective seal.
Failing that, have the pump and regulator investigated.
I'm sure Jim has given stripdown and rebuild directions for both, somewhere on the forum and not too long ago.

Don't take my word for it though, hang on a bit with anything more invasive than checking the returns to the reservoir and see if anyone has some better advice.

[citroenxm]

By leak we mean internal return leak.. not a leak you will see coming out onto the floor.