C5 Violent Suspension

mooseshaver · Post by **mooseshaver** » 06 Aug 2007, 11:52

Hello, this is from someone on the C5 Facebook site
"I own a 2002 Citroen C5 2.0 sx, it is a wonderful car apart from a strange suspension problem which Citroen are struggling to diagnose and keep changing bits but it doesnt do anything - the problem is when the car is parked and I lock it the suspension will start to wurr as it does normally and then I can hear a air noise (sounds like a air baloon being filled) and then without notice the back jumps up violently and then settles - very strange any idea's ??"

I've never seen that before, didn't realise the suspension could move fast.

CTR · Post by **CTR** » 06 Aug 2007, 13:01

I think it is just the other words description of the known up&down
problem:

At some conditions (wear in front corrector, extra friction in suspension etc..) you may discover C5 doing "exercises" - doing up and down when parked (~20-30 sec interval)

This sometimes happens with my C5 if I park it _slightly_ Uphill + on a slight slope left to right. Moving it a few sm or rotating the front wheels a little - fix it. So I do not worry about it.

den169 · Post by **den169** » 06 Aug 2007, 15:21

Mine sometimes moves up and down if i leave the wheels turned,but never when there straight.

Post by **RichardW** » 06 Aug 2007, 16:19

It sounds like it must be a Hydractive 3+ car, and there is some problem with the electro valve meaning that the pressure does not equalise, then the valve opens and the suspension changes height very rapidly. Quite common on Xantias, but not (yet

) on C5's.

Post by **CitroJim** » 06 Aug 2007, 16:59

I wonder if Citarobics will work on a C5? It has to be worth a try if it can be done in a similar way to the Xantia. Has the C5 got a manual height control?

mooseshaver · Post by **mooseshaver** » 06 Aug 2007, 20:05

C5s Have electronic buttons for up and down. Press once to move one position in height. Four settings, Down, Normal, slightly up, top. Think they are the same as the Xantia's analogue control. If you leave it on low, and drive above 6 mph, the height increases automatically. If you leave it one slightly up, you can do about 24/26MPH before it moans and lowers. You can do 6 mph on max height.

Will ask em to try citrobatics.

Thanks for all replys.

SimonM · Post by **SimonM** » 07 Aug 2007, 10:25

My C5 has the old up & down issue. If I park it with the wheels on full lock to the right the front will go up and down like a YoYo

Once took it to have the tyres changed, was talking to the fitter about which tyres to have when a chap walked in and asked who had the silver Citroen as it was doing some strange things, I went outside to see a few bemused people staring at my car as it was doing its exercises

My road has loads of speed humps and the suspension automatically increases ride height, when I get into the drive and get out the car settles down and I can hear a hissing noise as though air is escaping, never fathomed out what this is.

With regards to the back jumping up violently, I have never had this when it is standing still but have had it when driving. Every so often when I brake, usually when going at less than 20, the back will jump up to maximum height and immediatley drop as soon as the peddle is released, it must look rather odd to those behind

mancuk29 · Post by **mancuk29** » 07 Aug 2007, 11:50

moonshaver, did you ever get your citroen diagnosed mine is doing the same and citroen are next to useless and cant diagnose it

ive had new height senson, new suspension lifters )the things which lift the car) and new ecu update - did you ever get yours diagnosed ?? if so what was the solution , I love my c5 so much and dont want to get rid of it but its a pain

mooseshaver · Post by **mooseshaver** » 07 Aug 2007, 12:09

Its not my C5 thats doing it. It ws someone on facebook who has been to a dealer, sorry.

C5IAM · Post by **C5IAM** » 11 Aug 2007, 22:50

The only time mine will jump up or down sharply is if I pull up and turn the engine off but keep my foot on the brake. As I release the brake, up or down goes the back. The brakes are obviously preventing the wheels from turning that small amount in order for the car to level off. Secondly, if parked on a diagonal slope, or one wheel is in a dip and the engine is turned off the car does bit of a performance to try and level itself up.

Post by **elma** » 12 Aug 2007, 00:07

My xantia used to go up when braking but it wasn't really noticable. Upon releasing the footbrake it would drop back to normal height violently.
It also used to sort of vibrate up and down when stationary.
The brake pedal also vibrated at a high frequency when braking (not discs or pads they were all new) which tickled my foot. This would happen if I pressed the brake when stationary with the handbrake on.

New accumulator sphere and lhm bleed cured the whole thing. Car wasn't ticking at the time, but just a bleed hadn't worked so tried ac sphere because it looked old.

Don't know a lot about the c5 but I hope this might help a little.

jorgy · Post by **jorgy** » 12 Aug 2007, 01:18

**ATTENTION**

New height sensor(s) on a C5 need setup on the Cit computer!!! They don't just work "from fitting". Many Cit dealers unbelievably don't know this! Takes 5mins!

regards
George

AndersDK · Post by **AndersDK** » 12 Aug 2007, 01:23

Before further handing over experiences from the Xantia, please note these very important differences from the Xantia :

1) the C5 brakes are completely conventional, using DOT4 brake fluid and the common and garden vacuumservo assist. There is no hydraulic interconnection between rear suspension and rear brakes on a C5.

2) the suspension is no longer controlled by hydraulic valve height correctors. Instead there is a height position sensor potientiometer telling the suspension ECU when to charge or discharge each axle suspension to correct the height - by way of electrovalves.

Still the rear arms and suspension cylinders would be very similar to the Xantia, suspective of developing the same fault types. Like worn out and binding/sticking rear arm pivot bearings.

I believe that there is a general mis-assumption that the C5 would last almost forever in the suspension - because of the new sphere types used - and announced as "lasting forever".
It may be very true - that most of the C5 spheres will last 10 years no problem - with the odd exemption proving this rule.

But the rest of the system will surely prove to be as ever-lasting as the Xantia is

Post by **elma** » 12 Aug 2007, 01:30

Thanks Anders. HAd no Idea about the brakes (dissapointing really). Guess I'll just watch c5 stuff from now on in case I ever have one.

jeremy · Post by **jeremy** » 12 Aug 2007, 07:01

Anders - presumably if C5 uses potentiometers to control the height the things become noisy after a while and will need replacing - just like a radio volume control. Is this noise the cause of strange behavior?

Do you think if the appropriate unit were dismantled the potentiometer would turn out to be a readily available component which could be simply fitted?