C5 strange suspension behave..

[alex666_slo]

Hello guys.. I run to a problem with my C5 2005 1.6HDI wagon.. started with a fact that new tyres warn more on outside .. all four. So I watch what my car do and found out the following:

1st symtom:.
Car drives in higher position then normal. When I stop is stays high (but lower then if I would set it to mid up position) but if I just open close doors it goes down. If I park it and turn off engine it will stay up until I unlock it.

2nd symptom:
When car is on flat surface, out of gear, no handbrake and engine on. doors closed and I load it on rear side it will go down and then up to righ level. If I remove load it will go up and will stay there until I open/close doors or lock/unlock it.

3rd symptom:
engine running, hand brake on, out of gear. Front end starts to go up and down.

Oil level is o.k, battery is o.k... I checked the corectors and apply some grease to small rods that are connected between correctors and bar. Still same.. My next guess are defect of both correctors as there is no errors in the system.

Any suggestions? Thank you. Alex

[myglaren]

The height corrector potentiometers have been known to be affected by dirt/water ingress and also burning of the tracks.
Reportedly easy to change and inexpensive.

Condition [2] is normal.

Condition [3] has been observed under various conditions but mainly when static on an incline or with the front wheels turned to the left or right rather than straight ahead.

Welcome to the forum

[alex666_slo]

Thank you for fast response.. for condition 2 shouldn't it return to normal position after load removed? In proces of heigh control it says it should return to right heigh.

I'll checked if up/down movements are present when wheels are straight and report.

Alex

[myglaren]

Indeed it should. I'm afraid I misread that part.

[alex666_slo]

Thanks for fast replay.During driving it feels like when drive in middle high position.. I'm electronic by proffesion and what looks strange is that control unit seems to know that position is wrong otherwise it would not change it just by open-close doors or lock unlock... except.. except if the spike caused with that on power lines would change the sensor readings... I need to check that.. another issue is the fact that since I have that car (4 years now) it was always a litle noisy on rear axe.. I have feeling that increased lately. I'll check axe bearings etc over weekend but I think that can't be the reason.

[BX]

If it takes you a while to remove the load after you open the tailgate and the car is stopped and no doors are opened or closed in that period, the BSI is likely to go to sleep in order to conserve battery power. As you remove weight from the car the car will rise on its suspension. This is normal. Opening or closing a door wakes up the BSI. The height correctors are read and the height is corrected.
I have no idea why it sits higher than normal when driving.
Correcting the height is normal immediately after unlocking and thus waking up the BSI.
As for the tyre wear have you checked your pressures. Low pressure causes both shoulders to wear but oftentimes more on the outside than the inside. The 30psi. Which is present on many fitting machines is not enough.