Citroen C5 - potentially stuck in Sport mode / harsh ride?

[wbgenetic]

Hi Guys,

I've been dreading a smoother ride for my Citro over the past few months since I've bought it.
My car has H3+ = 6 spheres.
4 of them were already changed with spheres @55Bar from Xantia and the ride did improve a bit (the old original spheres were making noises when shaken).

Now I compared my ride with a C5 2006 estate (2.0 engine with auto gearbox) and it seemed like it was riding a tad smoother (spheres were changed in the past but 4+ years for sure).

What could I do to improve the ride and what could be the problem potentially?

- Height of the vehicle?
- Central spheres?
- Could it be that a hydrocylinder is stuck in sports mode hence the harsh ride -> always using the central spheres

Any suggestions will be more than appreciated.

Wishing you a great day and greetings from Bulgaria,
V.

[GiveMeABreak]

Hi and welcome to the forum

The spheres are not meant to be swapped from a Xantia - so you may have different pressures to start with - these will vary depending on engine and H3 / H3+ so we would need to know you VIN or engine type to begin with. The centre spheres are of course a different pressure too, 62 Bar depending on model again.

Sports mode deactivates the central spheres so the car is riding on the 4 corners only - not the other way round. So if your Centre spheres are shot, then you will be in sport mode effectively all the time.

[wbgenetic]

Hey Marc! Thanks for the quick response.

I do not know the status of the central spheres but I reckon they are indeed sort of dead. The car does feel like being in sports mode all the time.

Now have driven it with a lexia attached and the sport button does change 3 values to 100/100 and to 0/100 when off. The mode stays to 'soft' all the time though. The road seems to be indicated correctly from Rough to Normal and back.

The car VIN is VF7**************[VIN obfuscated, can be read by forum staff] so the original spheres are 52 bar front and 40ish - back.

The front xantia spheres are 55bar, the rear I do not know but close to the originals. This was suggested by a local citroen repairer. Again this did improve the ride a bit... But not by much.

Couldn't he vehicle height affect the ride quality?
Also could it be that the electrovalve gets the signal but is stuck and does not activate the middle spheres?

[GiveMeABreak]

Lexia will only show that the stiffness regulator is energising or not- but it won't know if the centre spheres are low on gas or completely shot - so that may still be suspect.

Anyway your spheres should be:
Front corners:
385 CM3 - 52 BARS (Part 5271 H7)

Front Centre Sphere:
AV 385 CM3 62BARS (Part 5276 16)

Rear Corners:
AR-385 CM3 44BARS (Part 5276 22)

Rear Centre Sphere:
AR 385 CM3 44BARS (Part 5272 66)

The ride height should be within the tolerances - you can check with Lexia under the suspension ECU - there will be a value for reference heights (recorded in steps not measurements) and then what the system reports it as.

[wbgenetic]

Thanks,

will give it a shot with Lexia regarding height.

In another forum another potential suspect is a stuck Hydroactive valve ...

[Peter.N.]

The central spheres are mainly responsible for the soft mode, if they are flat you will notice little or no difference between sport and normal.

Peter

[wbgenetic]

But if they are flat I will be more or less stuck in sport - which would explain the rather Passat-like ride that I currently experience:?

[GiveMeABreak]

If they are flat - then you are effectively riding on 4 spheres - akin to sport mode yes, as you are knocking out 2 of the spheres in the circuit. Ignoring the straight ahead ride quality for the moment - try going round a twisty stretch of road with lots of bends and then try switching to Sport mode to see if there is any less roll. If it is about the same, then it could be the centre spheres, as you already know that the stiffness regulators are working from Diagbox when you tested them.

[wbgenetic]

Yes, ride and roll remain the same regardless if Sport mode is switched on/off (at least based on my subjective perception....)
Guess I will just order the 2 middle spheres if this is the case.

Could however the 2 middles spheres be isolated due to a stuck valve Wouldn't this sort of give the same result. The valve gets the signal, but does not respond ... as is stuck

[GiveMeABreak]

I'm trying to recall if I've heard of this problem on the C5s specifically and can't recall off hand. It was an issue on the Xantias and XM - but I think things improved somewhat with the C5s.
The only way to know is if you get them off and get them tested - which means having the car out of action while you are getting that done. - but at least you'll know - or you could say ok, I've had them for nearly 13 years....

[Peter.N.]

The two centre spheres do the most work when in 'normal' mode so they can have a shorter life than the corner ones. My experience has mainly been with XM's but I think the set up is similar. If they are flat changing them will make a dramatic difference.

Peter