C5 front spheres !

[IgorI]

Hello everyone! I am new here. I found this forum by chance and I really liked it. I want to ask a question. Maybe it has been asked before, I read the forum and find some answers, but I have not found a specific answer that is similar to my question. Please do not be biased towards my post. I will be grateful for any help.I have a Citroen C5, 2012, 2.2 liter engine, automatic, diesel, station wagon. 19-inch wheels, by the way. The problem is that when I drive over tram tracks or a speed bump, the front of the car starts swinging up and down and up and down. It bounces like a ball very quickly and with normal amplitude, and at times it seems like I'm going to be thrown out of the car. The back goes normally. I went to the official dealers, they did a computer diagnostics - they didn't find any errors. However, I didn't expect anything clear from them. I went to a private service station that deals with French cars. There they suggested that this happens because the front spheres no longer have the required pressure or have already become unusable. The solution may be to replace the front spheres. They may be right. And I also have 3 spheres in the front, as I understand it - right/left and the central one, which is responsible for comfort. Nobody here pumps up the spheres - we don't have many Citroens with pneumatics. I just looked at the Poles' I.F.H.S. spheres. If that's the right line of thought, I'm thinking of ordering them. I don't understand which of the spheres is responsible for such smoothness of driving over bumps - left/right or central front. And at the service station, private owners set the height of the front and rear suspensions, but nothing cardinal happened. Before that, I had a C5 2-liter diesel, station wagon, manual. Everything worked just fine there. So I have something to compare with. My wheels were 17 inches there. Maybe that also affects the smoothness? I've written a lot. That's all, I think. I'd be grateful if you could find a way to tell me what could help me, which way to look!? Regards, Igor.

[Kees]

@Igor:
You can find several posts here from my hand about this issue.
In general you can say, at the front all 3 sphere's are responsible for the suspension, but the center sphere provides the soft suspension.
The system switched this one of under several condition.
But when you experience the problem you described, the best way is to replace ALL 3 sphere's, the brand IFHS is fine,and much cheaper then the original.
Because it's not easy to replace the center sphere, some mechanics don't replace this one.
There's also a post from me here how it can be done, without remove the subframe.
One thing besides, i don't understand why somebody put 19 Inch low profile tyres under an C5.....
Greetings,
Kees.

[IgorI]

Dear, Kees! Thank you for your quick response. Yes, I continue to study the forum and find a lot of useful information here. As for the 19 wheels, I bought the car last year in Belgium. At the same time, such wheels were already on the car. On the one hand, they are beautiful, but when driving, they behave more rigidly than the 17-inch wheels that I had on my last Citroen C5. Especially in winter. As I understand you, it probably makes sense to replace not only the front side spheres, but also the front central one. I really hope that replacing the spheres will change the behavior of the suspension. Especially when you know how the suspension with working spheres should work.

[Kees]

@Igor:
The problem with the C5 X7 about the difference in suspension with for example the XM and XANTIA is, that the center sphere is switch off to quick and to much.
For example it switch to stiff if you add throttle or apply the brake, also with an amount of steering and movement of the stabilization rod.
In the past i connected i LED on the front stiffness regulator, and noticed that the center sphere was so many times switched off.
I came to the conclusion for myself to disable this system, to disconnect the stiffness regulator's at the front and back.
For me it's works fine, so i have a car with the hydraulic 3+system whiteout the "+".
Greetings,
Kees.

[steveclv]

Kees
I am interested in your modification to disconnect the stiffness regulator(s) as I prefer to always drive with the soft suspension. Do you have any details of how to do this without upsetting the cars computers please?
Thanks
Steve

[Stickyfinger]

I would think that this will greatly "upset" the handling of the car when it is most needed......... I would label it as an "unsafe" modification.

Maybe nice on normal roads etc, but when sudden action/change of direction is NEEDED I would be very concerned to be inside such a car.

IFHS spheres are fine.

????? ??????? !

[Kees]

@Steve:
Because i have a V6 3.0/24 the front stiffness regulator is on the right front.
So i disconnected the connectors from the front and rear stiffness regulator.
The system however checks the connection all the time, so i connect a resistor 10 Ohm/10 Watt, to fool the system.
When the front stiffness regulator is on the left side behind the left front wheel, i don't know if you can reach the connector, if not, then you have to find the connection on the big connector on the BHI on top of the LDS pomp.
I know that here on the forum you can find these pin outline with numbers and you can check with an multimeter the resistant of the coil, this is 8 Ohm.
Greetings,
Kees.

[GiveMeABreak]

Personally I wouldn't change this myself - the car is designed to handle according to the the standard setup - going into firm mode when cornering or more importantly vehicle stability when handling emergency braking, skid avoidance etc. Disabling it will therefore affect the stability management of the vehicle and therefore the safety.

[Kees]

@ stickyfinger:
There is NO problem about the roll of the car!!
When you look at the system of older types like the BX, XM, XANTIA and C5 types without the hydraulic without the active system they just have only 4 corner sphere's.
People who ride this cars in the past are disappointed about the suspension behavior of the C5 X7.
In the past when i look at cars with conventional springs i wonder how it's possible that they took bumps smoother than my car.
As i say, i find out in this case the the system switched off the center sphere, and became a stiff suspension.
So i just tried the behavior of the car in the manner I described, and this is much better.
Greetings,
Kees.

[Kees]

@Marc:
I understand what you mean, but when you drive a car with metal springs, the car reacts when you accelerate or break with reaction front/rear and take bumpy roads smoothly.
The C5 X7 doesn't, because as i say earlier the 3+ system switched the center sphere of almost with every chance of what the driver do.
It's not that i only checked with the led on the stiffness regulator, but also real time with the diagbox.
I agree with you, that you want a stiff suspension in critical situations, but not when you break normal or change the throttle pedal or steering the corner.
It seems to me that Citroen has developed a great system over the years, but now they keep developing something in the wrong direction.
Let me give you an example about the XM in the ha H4 computer the back center sphere was switch off when you apply the brakes, or when the front ride over a bump, this keeps the car horizontal, but stiff suspension in the ha H5 they remove this item.
It was better that the threshold between the parameters for soft/stiff has an other level.
I know, that Citroen provides a different program of the BHI for the C6 if the costumer complained about the suspension.
Greetings,
Kees.