Anti Sink Valve C5 X7 Exclusive

[Jonesy]

My 2009 Exclusive Tourer has developed an intermittent tendency to sink at the back end when parked over the last week. Seem to recall mention of an anti sink valve and or sphere? There do not appear to be any fluid leaks and if I restart the engine and adjust the suspension level to high and back to normal it seems to stay up. Question is, shall I just put up with this or is it something which could have further consequences so should be fixed? If so, any ideas how much it might cost to rectify? Pleased to hear.

 

Best Regards

John

[paul.h]

Any work on the suspension hydraulics only seems to need 1 hour labour but the parts can be expensive. You would be best asking your dealer for the likely cost of the various bits but unless sure of which is faulty, it may not be a good idea to buy anything yet. The rear firmness regulator might be part 5277N7 and 2 spheres fasten to this - the part numbers of these vary across the models - 527291 for the estate and 527278 for the saloon. If could also be a rear strut that has an internal leak. Any part numbers should be checked using your VIN.

 

Whether or not it gets worse if not repaired, I do not know. I had a leak on a rear strut and the back would sink only slightly and left it a year before replacing it. It did not get worse but I got fed up of the slight oil drips on the floor.

[Jonesy]

Thanks Paul. Have heard that when this happens Citroen dealers put it on the diagnostics and nothing shows up so unless they are savvy will probably get nowhere. Might give them a call to see if they have dealt with this before. As mentioned, no leaks. When it does sink, and it sinks right down on the bumpstops at the rear, after opening a door the electric pump whirs away and then after a while it suddenly jumps up all in one go much to the shock of passengers! When it does sink it does so fairly rapidly after turning the engine off. But... fingers crossed.. it hasn't done it for the last couple of days. It really is an all or nothing fault. 

[paul.h]

You could also check the lds suspension fluid level. With the suspension at its lowest setting, the level in the tank should be at the bottom of the tank filling neck strainer. When you open the lid there will be a slight venting of air so slacken it gradually. If you ever jack the car up, always raise the suspension to max height first and if the wheels are to be hanging, then the lds tank cap should be slackened before using the jack and not tightened until the wheels are back on the ground - failing to do this might lead to the lds tank splitting. Tyre fitters might not know this.

 

Also do not go under the car without using axle stands since if a height sensor is caught it can quickly lower before you can get out of the way.

[Jonesy]

So... problem went away for a couple of weeks but returned. Can sink quite quickly after turning the engine off but playing with the up and down height adjusters usually got it back on the level again. Until last Saturday (thankfully on my driveway at home) when I tried on about 6 occasions and the rear end would just not raise off the bump stops at all. Could hear the pump going and a sort of whooshing noise from the rear. Shook it, rocked it, lifted it up by the bumper, bashed the thing between the two central rear spheres with a broom handle but refused to raise. Tried again on Sunday and after about a minute the rear end 'jumped' up to normal height.

 

The sinking I can live with but the not raising again afterwards is a bit more serious. Not wishing to allow this to happen to my wife whilst away from home booked it into a Citroen dealer where it is today. Needless to say it will not sink for them. Report is there were a few error codes for the suspension and they will 'start' with replacing the height sensor at I don't remember at how many £'s plus £90 for looking at it. Seems to me this is going to be an expensive business and resolving the problem may be a way off?

 

Surely somebody on here has had this problem before and knows the solution before I just throw hundreds of £'s at it for a main dealer to replace everything on a trial and error basis?

 

Would love to hear!

[paul.h]

The height sensor might be a good place to start. On our 2007 C5 the suspension pump would sometimes kick in and raise the car slightly when moving slowly or just stopped. It was not dropping down much though when not being used. The other day I greased the height sensor arm ball/socket joints and now this does not happen and the ride seems a lot smoother. In my case it could be the arms were sticking a bit.

 

Have a look at this similar topic in which it turned out the pump was at fault.http://www.citroen-owners-club.co.uk/citroen/topic/24488-rear-suspension-droops/

[Higgo]

I also seem to have this problem. I googled for solutions and found this relatively recent thread so thought I'd jump on it.

 

Mine sinks when parked most of the time (but not always) and reverts to correct height when I start the engine. As an aside, I thought I'd read that the height adjusted when the driver's door opens but I definitely don't hear the pump until I turn the key. 

 

As long as it doesn't get worse I have no issue - car looks low when parked but is fine to drive - however my concern is that it will get worse. We're driving to the Alps and back in a few months and don't fancy doing it with the rear suspension on the bump stops.

 

Am I right (from the other thread referenced above) that:

• the most likely cause is a faulty anti-sink valve?
• the anti-sink valve is integral to the pump assembly?
• the pump assembly is expensive?

 

p.s. 2008 C5 X7 Exclusive Saloon

Edited October 26, 2018 by Higgo

[coastline taxis]

your running on 9 year old suspension fluid. it losses it viscosity and starts to compress and allow the car to sink. seem to remember lds fluid has a 4 or 5 year lifespan. change your fluid 1st

[xpag]

I'm going to follow this thread. Very occasionally. My rear end falls to the bottom stop.and will only rise again by me raising then lowering to normal with the console switches. However if I load the car with people or attach my caravan the suspension lowers significantly and does not adjust automatically. I have to raise and lower using the switches. The car then drives fine. Busy trying to load Lexia3 onto an xp laptop. It's a nightmare.