Xantia stuck in hard mode

[xantos]

Now I've noticed that the back height regulator is leaking...

EDIT: I was thinking maybe I have mixed the hydraulic lines going into the height regulator?

[Mandrake]

Xantos, a few pages ago I suggested the 1N4008 as a suitable diode for the diode mod, I quoted this number in error and it has been brought to my attention in the below thread, that it is not a suitable type:

http://www.frenchcarforum.co.uk/forum/v ... 27#p374827" onclick="window.open(this.href);return false;

1N4008 is in fact a low voltage low current signal diode which is most certainly not suitable for the task. Any of the types from 1N4001 through to 1N4007 are suitable however.

What is the exact type number of diode you used ?

[xantos]

I am using 1N4007 diodes, so that's ok.

The car was really soft after making the "10 minute mod" and cleaning the filters and height correctors. It took some kilometers to get to soft but eventually everything settled down and the car was really a joy to drive.

But then disaster! When driving I felt that something was wrong with the back end of the car. I pulled over and LHM was pouring out from the activa cylinder! One bolt holding the activa cylinder and the rear arm fell out and the other got broke. The hydraulic pipes going to activa cylinder were pressing against the chassis and the LHM was leaking.

I managed to fix everything and it seems the hydraulic pipes are not damaged as they are not leaking.

And back to harsh ride again and electrovalves malfunctioning. I believe that after a few hundred kilometers everything will be back to soft again. Hopefully.
I have noticed that every time doing something on the hydraulic I have problems afterwards regardless of de-pressurizing the system and doing citroaerobics 3-4 times.

[xantos]

I am really getting annoyed with this car's suspension

Having problems with the electrovalves all the time.
When they stop to function I just leave the car running and for a few seconds remove the F8 fuse in the engine compartment and they kick in.
But after a few miles just stop working. Sometimes front and back electrovalve are working and the activa not, but eventually it kicks in.

I have also noticed that the car is "jumping" up every few seconds when on stand (hard to tell when also while driving). Just for a fraction of an inch like the pressure is being accumulated and then released.
So probably the accumulator sphere has gone.

Also bought a Lexia and here is what faults activa ECU shows:


Erased all the faults, went for a ride, connected Lexia again and no faults were shown. Everything seemed to be ok, but in the morning after a few miles the electrovalves went off again.

Any ideas why this happens?

[xantos]

Forgot to mention that you can hear a ticking sound every few seconds and when it ticks the car bounces (just a fraction though).
High ticking started after repearing the bolts that got broke between the activa cylinder and rear arm.

Reading Jim's post a believe that might be the electrovalves itself that need to be cleaned and "springed".
I bet that I will brake something taking them apart

[Mandrake]

The large number of individual intermittent faults logged by the Lexia suggests to me that there is a bad electrical connection to the Hydractive ECU, have you used contact cleaner on the two connectors to the ECU ? Its extremely unlikely that all those different sensors are individually faulty.

More likely the ECU connectors are oxidised, or there is a fault in the power supply to the ECU, (bad ground or bad positive feed via the fuse box) or an internal fault in the ECU.

Did you go into the individual faults to get more details, in particular the Intermitent ECU fault ? What did it say ?

Regarding the clicking, where was the clicking noise coming from ?

[xantos]

The ECU connectors are ok, unpluged and checked them when doing the diode mod.

No didn't go into individual faults just erased them, but will connected Lexia again (maybe on Sunday) and I bet the same faults will be present.

The clicking is coming from hydractive control block or the main accumulator valve not sure... But it's not the electrovalves that are clicking as I would have seen that on LED's that are installed.

Like I said when unplugging fuse F8 the valves start to work. Like the ECU needs a reset. Lexia couldn't connect to activa ECU when the valves weren't working.

[xantos]

Figured out where the clicking is coming from. It's from the main pressure regulator. It's clicking every 5 seconds sometimes click-click. I figure that I have a ruptured main accumulator sphere or that maybe I've damaged the seat for the pressure release valve. That would be a bonus...

The electrovalves are now functioning (3 days ) but the ride is not as it should be. Better than before but still...

Interesting is that I have lot's of bubbles in LHM when the car is on LOW. When the pressure valve is unscrewed there are no bubbles at all and on RIDE height there is a bubble here and there (also on HIGH). My thinking is that if the pipe from the LHM tank and the pump is leaking there should be bubbles on every height the car is set, right?

I have changed the rear arm bearings but the wheel still standing like this | \ . Is it possible that the whole arm is "twisted"? Inspected the seats for the bearings and they seemed to be ok... I don't know the car's history so maybe it was crashed. Is it possible to "straighten" the arm? Of course with a special tool from a repair specialist (muscles and 20 pound hammer )...

[Mandrake]

Like I said when unplugging fuse F8 the valves start to work. Like the ECU needs a reset. Lexia couldn't connect to activa ECU when the valves weren't working.

I assume you mean when unplugging F8 and then refitting it the valves start to work ?

You didn't mention before that the ECU stops responding to the Lexia when the electrovalves stop working, and then starts working again after the power has been removed and reconnected.

This really does sound like either you have a marginal power supply to the ECU or the ECU itself is faulty. No electrovalve faults should cause the ECU to stop responding to queries by a Lexia. It's almost as if the ECU is crashing and requiring a reboot.

[Mandrake]

Figured out where the clicking is coming from. It's from the main pressure regulator. It's clicking every 5 seconds sometimes click-click. I figure that I have a ruptured main accumulator sphere or that maybe I've damaged the seat for the pressure release valve. That would be a bonus...

The electrovalves are now functioning (3 days ) but the ride is not as it should be. Better than before but still...

Another possible source of rapid pressure regulator clicking is leaky electrovalves - on my previous Xantia the front one was internally leaky but only in the on/soft state, leaky enough that the pressure regulator cycle time was reduced to about 8 seconds.

Usually they don't leak when they're in the off/hard state so try removing the Hydractive ECU fuse and see if you still have rapid pressure regulator clicking. If you don't it'll probably be a leaky electrovalve, if you still have the same rapid click rate it could as you say be either:

* Flat accumulator sphere
* Bleed screw not sealing properly as you suggest - try loosening and tightening it a few times with the engine running, and don't over tighten, just nip.

Interesting is that I have lot's of bubbles in LHM when the car is on LOW. When the pressure valve is unscrewed there are no bubbles at all and on RIDE height there is a bubble here and there (also on HIGH). My thinking is that if the pipe from the LHM tank and the pump is leaking there should be bubbles on every height the car is set, right?

I would have thought so, yes.

I have changed the rear arm bearings but the wheel still standing like this | \ . Is it possible that the whole arm is "twisted"? Inspected the seats for the bearings and they seemed to be ok... I don't know the car's history so maybe it was crashed. Is it possible to "straighten" the arm? Of course with a special tool from a repair specialist (muscles and 20 pound hammer )...

Keep in mind that some negative camber is normal on the rear wheels, I don't recall off hand what the figure is without looking it up, but a small but visible amount of negative camber on the rear wheels is normal. Are you getting unusual tyre wear ?

[Dommo]

Usually they don't leak when they're in the off/hard state so try removing the Hydractive ECU fuse and see if you still have rapid pressure regulator clicking. If you don't it'll probably be a leaky electrovalve, if you still have the same rapid click rate it could as you say be either

Just to throw a curve ball in here, my rear electrovalve only leaks internally when it's in hard mode! I've replaced it with 3 different electrovalves and it still does it, I've done the diode mod just to make sure, it still does it. I did the "10 minute mod" on the forum with the LHM tank, still does it!

[isisalar]

Having done a lot of peering into my LHM tank recently, and still with bubbles being generated, I can assure you that there are always more bubbles in the tank when the car is on low. I figured that by putting most of the LHM/bubble mix from the system into the tank most of the bubbles are then in the tank and gather at the surface. 10 mins ticking over will generally clear them.
Replacing the tank to pump feed pipe is not difficult, Ive recently posted about it if you have a look.
Cheers
Paul

[Mandrake]

Paul, there are no bubbles at all on the oil surface in the main part of the tank on mine at any ride height. Zilch. Nada. Zero. Still as a pond on a calm day. There is a small amount of bubbles within the top of the return filter though.

Could it be that your tank is overfilled causing the oil level to be above the top of the filter when the suspension is at minimum height ? That way the bubbles may get through the gap between the top of the filter and the riser, rather than being contained within the filter...

[isisalar]

Ah yes Simon, but you don't have a bubble generator in your system as Xantos and I do. I played around with the pressurisation screw just now and it was astonishing to see the state of the LHM when the pressure was released. There were literally millions of microscopic bubbles throughout the LHM, making it look a bit like a pale green metallic paint. These dissipated whilst ticking over for about 10 mins but returned when the system was pressurised again. I think the pipe replacement has cured air leaks from there and what I have now are what is coming from the pump( I'm praying), the oil and the air having been well and truly pulverised by the pump repeatedly into a sort of liquid mousse. The o rings should be here tomorrow and hopefully that will be the end of my suspension woes.
Plenty more jobs lurking though.
Cheers
Paul
PS tank level perfect

[cam205gti]

I know this an old thread but what happened here? Any results?

Ive got lots of bubbles and very similar issues as in this thread. My car is a CT with the HA2 system.