weird stuff with H3 C5 II

viorelovidiu · Post by **viorelovidiu** » 19 Nov 2009, 08:59

Hello!

I`ve bought in april this year a C5 II 2005 - my first car and fortunately i have had a lot of problems but minor except hydractive part... which is H3 (not plus). When I see "Her", I have felt in love... but front side was down - you cannot fit your hand between wheel and flyweel... when i get inside it starts going up. Even with engine started at every 2 minute i can sense it how going up (the acuator is correctin height all the time; with engine turned off in 2 minutes is completly down (on front side).

I was going to service - after 5weeks i got entire hidraulic sistem (computer-pump-electric part) which is located under LDS recipient. costs - 1000euros
the result? 3 days was perfectly fine and after that at every 2 minutes keep comin down on front side exactly like before

i was coming back to service - they remove the right front hidraulic cylinder (telescope) and "cleaned up a bit", mounted it back and since then car needs one night to get lower not much as before but enough to sense one or twice per day how front side is going up when driving whitout reason. because of that sometime i feel my car too harsh over road and other times is perfectly smooth even on the same road.

last time i went to my dealer here - they have found the acuator on front side to be the problem - i got it replaced and no changes afther that.

my car have had only 35.000km and it stayed a lot in garage - very very long time... i think that caused problems with suspension.

today i bought a second hand telescope to replace that one the service "cleaned up" a bit...

any ideas after reading my story?

Thank you so much!
Ovidiu

fred1 · Post by **fred1** » 19 Nov 2009, 15:54

Hi,

Sounds like the front height corrector.

On the C5 this is a potentiometer linked mechanically to the anti roll bar and electrically to the suspension ECU. As the car tries to go up and down the potentiometer signal changes and the ECU compares it with a pre set value and adjusts the suspension height accordingly to try and keep the car at the set height.

The potentiometer track wears with time and you get a broad dead spot in the middle where the potentiometer wiper spends most of its time. This causes the suspension to "hunt" up and down every few seconds.

Similar arrangement at the rear and both potentiometers are the same.

They cost about £35 each and take only a few minutes to change. Just one locating screw, and electrical connector and a small ball joint to release.

Regards

John

viorelovidiu · Post by **viorelovidiu** » 19 Nov 2009, 17:51

fred1 wrote:Hi,

Sounds like the front height corrector.

On the C5 this is a potentiometer linked mechanically to the anti roll bar and electrically to the suspension ECU. As the car tries to go up and down the potentiometer signal changes and the ECU compares it with a pre set value and adjusts the suspension height accordingly to try and keep the car at the set height.

The potentiometer track wears with time and you get a broad dead spot in the middle where the potentiometer wiper spends most of its time. This causes the suspension to "hunt" up and down every few seconds.

Similar arrangement at the rear and both potentiometers are the same.

They cost about £35 each and take only a few minutes to change. Just one locating screw, and electrical connector and a small ball joint to release.

Regards

John

hi john

i`ve already replaced the front height corrector (i named it acuator) and i get rid of what you describe "hunt up & down every few secconds, but this happened to me very few times. still i have these simptoms: in the morning i saw that the front side is lower than rear side, like is loosing pressure; sometimes in traffic i can feel how raised up a bit not the hunt up&down - like loosing pressure.
over night i`ve left 2 botles to collect lds from retour pipes of each front telescopes, in the morning i`ve found in both botles an amount of 5-7ml of LDS oil. is that normal? should not be completly dry?

what i cant understand - the hidraulic telescope is a completly closed sistem, how the service could cleaned up inside it and after that the front side is going lower in matter of days but not 2 minutes like before...

next week i`ll replace that telescope with a second hand one to see the results..[/img]

viorelovidiu · Post by **viorelovidiu** » 19 Nov 2009, 17:53

there is a picture how I found my car lowered on front side every morning

is noticeably lower than other C5s in my town..

fred1 · Post by **fred1** » 20 Nov 2009, 08:16

Hi,

Sorry I misunderstood your problem.

Looking at your photo, its hard to be sure, but it looks like the car may be too high at the rear rather than low at the front?

John

viorelovidiu · Post by **viorelovidiu** » 20 Nov 2009, 08:31

this picture is taken after 12hours since the car has been parked. when i stop my car both sides (Front &rear) are at the same height and stays in this position for almost 4-5 hours when the front corrector keep correcting till the computer will shut down power (economy mode).
I can assume that is a very small leak of pressure (air or lds - not enough to leave spots on road.

how can i check for leaks?

DickieG · Post by **DickieG** » 20 Nov 2009, 09:48

viorelovidiu wrote:how can i check for leaks?

Find the relevant LDS fluid return pipe for the front suspension and observe the flow rate by removing the pipe, if all is well it should do little more than drip.

viorelovidiu · Post by **viorelovidiu** » 20 Nov 2009, 10:08

DickieG wrote:
viorelovidiu wrote:how can i check for leaks?
Find the relevant LDS fluid return pipe for the front suspension and observe the flow rate by removing the pipe, if all is well it should do little more than drip.

sorry, but i`m not familiar with "more than drip"

i`ve removed return pipes once, the left one it was under pressure and dry and the right one was not under pressure and wet. Leaving for 12 hours into 2 bottles i`ve collected about 5-7ml each. My car was parked at normal position all this time.

sounds like a right telesecope with problems?

cachaciero · Post by **cachaciero** » 20 Nov 2009, 13:31

viorelovidiu wrote:
DickieG wrote:
viorelovidiu wrote:how can i check for leaks?
Find the relevant LDS fluid return pipe for the front suspension and observe the flow rate by removing the pipe, if all is well it should do little more than drip.
sorry, but i`m not familiar with "more than drip"

i`ve removed return pipes once, the left one it was under pressure and dry and the right one was not under pressure and wet. Leaving for 12 hours into 2 bottles i`ve collected about 5-7ml each. My car was parked at normal position all this time.

sounds like a right telesecope with problems?

You can't really do that on the C5, the pressure and the return line are the same bit of pipe back to the BHI, inside the BHI it is connected to two electro valves one to raise and one to lower, this is the same for the rear and the returns (from the "lower EV's) go back to a common return line to the resevoir.

The only thing that can be done is to disconnect the common return from the BHI and connect it to a separate container, put the suspension on max high and leave it for a while anything more than a few drops in the container means that one or more of the electro valves in the BHI is leaking. In this case you will need a new BHI.

Any leakage around the cylinder (telescope ?:-) would only show as fluid in the small diameter drain pipes from the gaiter.

cachaciero

viorelovidiu · Post by **viorelovidiu** » 20 Nov 2009, 13:41

I have a new BHI it costs me over 1000euros. I have had the same simptoms after replacing it like going down in 2 minutes no matter if engine was turned on/off. So I really want to exclude it....

i dont have any visible leaks on telescopes.

a telescope could have internal leakage whitout external simptoms?
LDS fluide cand induce any leakage if its dirty or its changed his properties during long periods of staying in garage?

thanks to all to be patient with me - but this problem drove me crazy already

Post by **myglaren** » 20 Nov 2009, 16:18

viorelovidiu wrote:this picture is taken after 12hours since the car has been parked. when i stop my car both sides (Front &rear) are at the same height and stays in this position for almost 4-5 hours when the front corrector keep correcting till the computer will shut down power (economy mode).
I can assume that is a very small leak of pressure (air or lds - not enough to leave spots on road.

how can i check for leaks?

If the car is locked then the suspension pump should not be running at all. You usually hear a whirr from it as you unlock the car as it adjusts the height.

Have you tried leaving it in the highest or lowest position?

viorelovidiu · Post by **viorelovidiu** » 20 Nov 2009, 17:35

good evening!

someday i went to a small citroen service with engine turned off but the car wasnt locked out. During almost one hour of chattin around car about suspension problems we sensed 2 or 3 times how hidraulic pump was working for 1sec and the front side rises slightly at that time like it was loosin pressure.

i attached a picture how i found my car and after unlockin it.

and a car seen in town

as you can notice both front and rear side are at the same height

if i let my car into higher position overnight i can notice the same event: front side is lower than rear side...

cachaciero · Post by **cachaciero** » 20 Nov 2009, 19:23

O.K Lets get logical

1/ Leakage.

In a cylinder there are two possible leakage paths, one back through the pressure / return pipe into the BHI and through an electro valve into the resevoir.
The second is leakage past the piston into the rubber gaiter, this drains back into the resevoir.

If oil is not going onto the road in a big puddle it is being contained in the system. Breaking into the drain pipe from the gaiter will give an indication of the amount if any of oil leaking past the piston while there will be some leakage here it should be very small, anything that looks like a steady drip would indicate a problem with the seals in the leg.

I assume that in your post where you talk about left and right pipes that it is these pipes you have checked for leakage and the values of 5ml in 12 hours seems reasonable to me, I would deduce from these figures that you do not have a problem with the cylinders.

As previously described disconnecting the main return to the resevoir will enable the quantity of oil escaping past the EV's in the BHI to be measured.

2/ Suspension Dropping.

The suspension is dropping either because there is a leak in the system OR because the system is driving it low.

But first lets consider whether we really have a problem

Now as regards the front dropping over a period of several hours I would regard this as normal, the front of the car is heavy with engine and there will be some internal leakages in the system and the suspension will drop a little or if well worn maybe a lot, I would not expect the car to drop significantly in a couple of minutes after locking the car.

When the car is unlocked I would expect the car to get to correct height within a few seconds and I would expect that until the car goes into economy mode the pump will run occasionally to make up any loss of pressure caused either by internal pump leakage or suspension demands made on the system, this is no different to previous generations of Citroens.

The pump running 2 or 3 times in an hour doesn't seem excessive to me.

If the front holds it's height for four or five hours with the car locked (i.e pump will / should be off) I would say that there is no problem.

3/ Car apparently changing height while driving.

The suspension is dynamic and the computer will change the ride height depending on road surface and speed, if it senses an uneven road surface it will raise the height a little and at higher speeds it lowers the front of the car to improve handling.

Having said all of that do you think that you still have a problem and why?

cachaciero

viorelovidiu · Post by **viorelovidiu** » 20 Nov 2009, 19:59

cachaciero - thank you so much for this very well & good information which will represent a good start for checkin suspension when i`ll reach a citroen service next week.

I agree with all you say and I have to find which one is correct: "The suspension is dropping either because there is a leak in the system OR because the system is driving it low" - lexia could told me if doing so or not?

But in my mind I still have a big question to you and all citrofans

Why removing right cylinder and how it can be cleaned and after remounting it, my car gets down after a couple of days and not in 2 minutes like before?
actually were 2 questions...

Post by **myglaren** » 20 Nov 2009, 20:15

I am going to observe mine more closely for a while and see if there are any similarities but I can say that I have never noticed the front or rear dropping significantly.

The struts are designed to leak slightly, otherwise there would be no need for a drain/return circuit.
I had a leak on mine about a year ago that was from the rear right return, it was just a slight nick in the bellows, the leak was very slight though, just wet the bellows and allowed a couple of drops overnight, less than a millilitre.

The pump on mine is completely inactive after locking the car - they will dance around if the car isn't locked, especially if parked on an incline or for some reason if the steering is turned a long way from centred.

I leave my car unlocked and the keys in all day at work, it never goes into economy mode unless I leave the CD player running.

After being left for a couple of days, it is no different than overnight. On unlocking the suspension motor runs for around 3~5 seconds, then again when I sit in the car, before it is started.

If I leave the CD player off. I can hear it run every 2~3 minutes.

How long has your car been behaving the way it is viorelovidiu?