2010 C5X7 suspension diagnosis

[seefyv]

Been trying to diagnose and fix the incredibly stiff ride of my 2010 C5X7. ALL seven spheres have been replaced by a specialist - system bled and refilled to correct level, etc.

Other symptoms;

Front right rattle diagnosed as suspension arm bush.
Front end doesn't always respond to height commands and is slow to do so when it does.
Car sitting about an inch higher on all corners than it is supposed to.

I've been given mixed information regarding the ride height issue. I've been told it absolutely must be done with a diagbox, and I've also been told I can do it via adjusting the collars attached to sensors at the roll bar - well today I had a go at the back one, without a proper ramp or lift there is no chance of freeing that bolt safely. I'm well aware of the risks working underneath this car regarding suspension so I didn't attempt it.

Would I be right in saying the extra ride height is causing extra pressure in the system that could be contributing to stiffness all round?

The specialist garage can't see me again for another six weeks, and it pains me to drive it like this. If I had a ramp or pit I'm sure I could sort the collars myself but I'm not sure that will get the result of a soft ride.

[Kees]

The best way, to correct the height is with the diagbox.
The normal height is 73 cm from the ground to the middle of the arc from the front fender.
If there is no diagbox, yes you can adjust the clamp on the stabilizer shaft.
what kind of spheres are there on you're car now? Type?

[seefyv]

They are IFHS spheres. At the front the car is around 76cm, rear is at about 75cm.

Does the height sensor get shifted over time causing it to drift?

[Kees]

Wel, this is an explanation, why the suspension is stiff, but it's not normal, that the height shift over time.
So you have to adjust it.

[KennyW]

The suspension adjusts itself to wear and tear but when you renew and part in the suspension set up it will be different .

I found this out to my cost when I renew the front wishbones to find the height way out. I adjusted it with the height sensor at the front by moving it by a tiny fraction. A slow and laborious task, eventually I got it within the correct parameters and finished it off with diagbox.

This took several days of trial and error, learning from my mistakes.

Kenny

[seefyv]

Interesting! I did get all new drop links in before I changed all my spheres so maybe that changed the geometry. Do you know what size the bolts are on the collars? I have a feeling mine will be seized so if is extract them I want to have the replacements to hand. I did put a spanner to my rear one to get the size of the head - being 8mm but I suppose it varies by the week the car was built

[seefyv]

So a little update,

Incorrect collar positions connected to the height sensors were definitely a cause of the stiffness! The guys I go to are pretty old school citroen guys, they measure top of wheel arch to ground - mine was at about 78 front and 76 rear - which should be, according to their methods, 73 front and 71 rear. The car looks so much better with the correct ride height and does indeed drive better. There is still some harshness to certain conditions, so next is to rule out valves sticking preventing switching to soft mode properly, the front tyres being a rubbish brand that I was forced to get after a puncture, and some suspension bushings.

The car does genuinely have some moments of greatness now when driving though, making the amount of money poured into it feel a lot more justified now that it's proved it can indeed waft, albeit with some residual harshness and stiffness that needs ironed out.

Now is the part where I admit spending 1000 on a 125k mile 2010 C5. I knew there would be some hassle, but lots of the main miles and age related items were already checked off between 75k and 85k miles, timing belt and associated bits, clutch, flywheel, steering rack, etc. Suspension was just left to rot apparently!

[Kees]

There is still some harshness to certain conditions, so next is to rule out valves sticking preventing switching to soft mode properly.

Sinds this is different from the XM/XANTIA, if the stiffness regulators are not with 12 Volt, then they are in the soft mode.

The X7 is just a bit stiff then the XM/XANTIA.