Rear Drops On Restart...

[Loopy]

Hi again,

Me and my tinkering... I changed the accumulator sphere over the weekend on my S1 and since then (although the suspension rises properly and the pump ticks far less often) if I turn her off and restart a few minutes after, the rear drops down pretty quickly, by that I mean faster thsn if using the lever to lower it. I've done 'citrobics' with the lever, both in auto mode and sport mode and it still does it, I'm wondering what I've done that could be causing this, have checked the new sphere is ok by using on the Xantia and no problems, and it was only that spher that was changed....

Any ideas?

Regards

Loopy

[rg]

Hi,

Usually a symptom of a shot anti-sink sphere.

r

[onthecut]

Hi. Loopy.

Won't be anti sink on a S1 --- there isn't any. I've had this on a S1 I had and, being lazy, just lived with it -- it always came back up in due course. I always presumed it was a valve doing something in the system once the ignition was turned on. Presumably having changed a duff accumulator, there is now more residual pressure, which accounts for the change. I've no doubt you will have the full answer by the day's out !

Mike.

[DerekW]

Not too familiar with the S1 but it sounds to me as if the rear hydractive sphere might be taking fluid from the wheel spheres. When stopped no power is fed to the rear electrohydraulic valve so the sphere is isolated. Turning on the ignition energises the valve. Quick way to check is to disconnect the lead from the valve so it can't open and see if the rear still drops on starting. I'm probably wrong but it's worth a check.

Derek

[rg]

Ah! Missed the "S1" bit!

r

[Loopy]

Thanks for your input guys;

After another session of Citrobics and a good run round the back doubles (switching in and out of sport mode) seems to have settled down and back to normal; I did find a post on the same problem in an old post which echoes my problem and from what I read there is a possibility that I have some soldering to do; there is a couple of transistors on the ECU board that are prone to burning out so I'm going to pop the ECU out over the weekend and see if there is any sign of excessive heat in that area of the board.

I've been trying to source the components so that if they do need replacing I can do the job. I am having trouble finding the transistors as Maplins have deleted from their stock and am looking on the WWW for them instead.

If anyone has a shop that sells electronic components in their area and wants to check if they have any, the part is VN05N, made by SGS-Thomson, and should anyone else in the NW London/Herts/Bucks area have the same problem but is wary of ruining their ECU I'd be happy to do it for them...... solder it that is, not ruin it!

Regards

Loopy

[DerekW]

Are these the ones that Noz has a stock of?

Derek

[Loopy]

Hi Derek,

I will drop Noz a line coz if he has some it would be very handy!

Thanks for the 'heads-up' on this.

Regards

Loopy

[xmexclusive]

Hi Loopy

Just a note of caution. I think that a 91 car has a different suspension ECU and does not use the VN05 devices that Noz has for later (Mk2) XM suspension ECUs.
You could first try to borrow a known good early Mk1 suspension ECU and try it in your car. Citroenxm might be worth trying to see if he can help.
The Mk1 suspension type also changed somewhere about 1991/1992. You can tell by the diameter of the LHM feed pipes to the top of the front strut heads. Early type are thin (less than 5mm OD pipe. Later Mk1 are thick (at least 10mm OD).
I am not even sure that Mk2 and later Mk1 suspension ECU's are the same.

Regards

XMexc

[citroenxm]

Hi..

Well what a coincidence, I just happen to be breaking a 2.0i Auto 1991 H reg. Just a few more bits to go and it will have to go..

A CRACKING AUTO BOX

Anyone want to rescue the box, free excellent engine with it.. They'll need to remove although I will help

Regards
citroenxm

[Loopy]

Hi CitroenXM,

I think you know what my next question is going to be.... Is the ECU going to be the same type as mine (2.0Si auto,RP is 4944)? If so, and it has no problems with the centre sphere switching,would you be interested in swapping for paper money?
Alternatively, could you verify the use (or not) of the VN05 component on the ECU?
Have I asked you about interior parts? I think I may have. If not there's a couple of bits I'd buy off you if it's got green velour.

Thanks for pointing me in the right direction xmexclusive, I want to deal with these things while the weather is not so good, and then when spring comes around I will concentrate on the aesthetics; paintwork, exterior trim etc. All being well she will be a real corker by the summer.

Regards

Loopy

This post has been edited by Loopy on November 23, 2006 09:44 pm

[jorgy9]

Loopy, can I, just ask out of personal interest, how often (secs) now your pressure regulator is clicking?

thanks
George

[Loopy]

Sure George,

Once everything has stabilised at drive height about 40 secs on tick-over....
Hopefully that's what eveyone elses does......Prior to the accumulator sphere being changed it was less, about 20 seconds.
I've kept an eye on the place where I park and there's no damp green oily patches below.

Regards

Loopy

[citroenxm]

Hi Loopy...

Car is gold.... with normal grey velour electric seats.. May strip the motors and seats runners (all intigrated) off to keep as spares, as I have sold ONE unit so far..

HOWEVER, the car being a Prestege was supposed to have leather, but what the owner did was swap the seats from his SD for the leather, but couldn't be bothered swapping the door cards, so I have 3 leather door cards( no wood ), the third in an Estate that I'm rescuing after christmas..

I'll get the ECU for you, and open it up.. What am I looking for, as far as "cooked" components go....?

Regards
citroenxm

[Loopy]

Thanks citroenxm,

I've attached a picture, easier than trying to describe which are the bits in question....

Cheers again

Loopy