Touch brakes and warning light flashes, at low speed no power assistance. Changed Doseur valve for new one, problem remained, swapped pump, still the same cleaned filters, same result. Spoke to Pleiades, FDV. Rebuilt FDV, now no power steering, pump screams as front rises, front drops immediately on switching ignition off. All new spheres fitted a few weeks ago. I am rapidly losing interest in this car.

Sounds like the pressure regulator, or even that the pressure release screw is loose or has been undone to far and the ball bearing has dropped out.

Peter.N.

Pressure screw tight and I do know how far to unscrew it when depressurising having owned Citroens for about 12 years, so ball bearing will still be in place. There being no definitive answer to the problem other than 'try so and so' which I have so far done to the tune of about three hundred pounds only to have the problem get worse, power steering is now non existent, I feel this would be better served parked neatly in a scrapyard where it can think about the folly of continually creating problems while the vultures remove whatever servicable bits remain.

Jim

Hi Jim.

Can I ask, did you buy an FDV or rebuild it yourself, not sure what difference it makes, but which model car is it? and where abouts are you.

There are only so many things that it could be (as you know) but I can sympathize as finding the fault can prove very expensive, as you've probably found out already, unless you can source good secondhand parts.

It's a 2.1TD Estate 1994 but the series 1.5 RP 6080 which shows up on Citroen's computer as series 2 but it is the mix and match version series 1. The FDV that was on it was the version where you cannot remove the plugs to get at the filters but I had an FDV sitting in my shed from when I broke a K reg on which the autobox failed. Bought the kit and took FDV apart and, after checkng with Pleiades and with the proper Cit technical sheets on rebuilding it, did so. All this has achieved is that when the pump kicks in now it screams, front is very slow to rise though it is no longer sinking on switch off but power steering has now gone completely. I had the choice a whie ago of getting rid of either this or my V70 like an idiot I kept this. I am sick to death of constantly having my head under the bonnet. There is a limit to how much more time and money I am prepared to put into this thing. Touch the brakes and warning light flashes still and this after having had hundreds spent on it. Even sourcing good s/h parts it's still the time and effort put into it, for no result. Yesterday, depressurised it, undone the pipes and it was on a mission to dump as much LHM as it possibly could, my arms were soaked, there was puddles of it running along the gutter. When I first raised this problem Pump, filters, doseur valve was suggested. Changed pump for known good one, ex K reg, cleaner tank and filters, re-bled brakes as I fitted a new Doseur valve, changed all 7 spheres for new ones. Car has got worse. It was Pleiades martin who suggested FDV as problem. I can see this becoming a change everything job which I am simply not prepared to do. Jim

Other more knowledgeable than me may know better but I'm more used to dealing with BX's. However no power steering at all would tell me FDV or pinion valve. But with the back pressure like you described, I can't see it being the pinion valve.

Come on you guys join in! what's the possibility of a pressure reg problem?

Hi Jim,

I'm a firm believer in doing as many checks as possible before spending money.

If the pump is working, things aren't doing what they're supposed to be doing and no fluid is appearing on the roadway, it must be going somewhere.

Dare I suggest that you check the return lines at the reservoir for excessive (ie continuous) flow? That way you should be able to pinpoint the unserviceable item/s.

Derek

PS Which model is it?
PPS Sorry, I wrote this about five hours ago and then had difficulty in posting it - only just able to re-establish connection with the forum.

Hi Jim

I would think that it is either the regulator or distribution valve. You can tell quite easily by disconnecting the return pipes from each one and see which has gallons of fluid coming out.

If you do scrap it, I may be interested. Where are you?

Peter.N.

I thought I was the only one that ran 2.1 diesels!

Peter.N.

I think you're the only one that can live with more than one of them

Jim

1/ you must have done it since u have the manual, but: have you adjusted the pressure on the refurbished FDV (there's a screw to regulate it afaik), strange you have no steering at all now.

2/ indeed most of times you can identify the culprit if you simply look at the returns, either at the LHM tank or at each element one by one. It's a shame you've already spent £££s for nothing.

3/ what do u think was the front dropping down when u switched ignition off? Sounds like electronic-related?

cheers
G

The car is in London. It was a beautiful estate in silver. We had fitted black leather interior and the wobbly web alloys but I was using it heavily and knew things needed doing but hadn't the time. Gear linkage detached and fault was gearbox balljoint got parts from Citroen but bought another car which is fatal. XM sat till MOT and tax expired. Not wishing to lose it I rented a double garage at £120 pm, room to work on it, but then filled it with so much junk I could not get to the car. It sat for two and a half years till they were about to demolish the garages. We rushed down and did the jobs. After sitting for all that time I put a new battery on and it started on the second attempt. Fitted all new spheres and it flew through it's MOT but had the annoying habit of pads low light coming on whenever I touched the brakes then I noticed slight loss of PS when touching brakes as parking. Coming back from walking the dogs an imbecile in a huge lorry, on the phone came straight out of side turning and smashed into rear quarter panel. My interest in the car took a dive. I had by then sold the V70. PS problem gradually got worse. Doseur was suggested along with pump and filters changed them all. Problem remained FDV was at fault, Pleiades. Rebuilt one, problem worse. Did notice that when unscrewing pressure valve I did not hear the hiss back. Rear rose quickly front crept up accompanied by scream from pump. It only dropped down the once, now it stays up but no power steering at all and light still comes on if I touch the brakes. It recently did a 1200 mile round trip to Scotland without a problem other than a pig to park. When I undid the pipes there seemed to be an excessive amount of fluid pouring out of the pipes as though there was still pressure somewhere.

Not knowing much about the FDV or pressure regulator internals, I have kept away to allow more knowlegeable folks to have a go.
If I had brake pad warning light coming on, I would replace the pads after checking the wires giving that signal. They could be rubbing somewhere on the disc, so giving a false earth.This could also apply to a short in the wire(s) from the brake pads onwards. I am surprised that they still exist - they usually break before much use. I've never yet had an XM with a working brake warning!
If it is not a wiring problem, then it must be brake pad wear that is causing the light to come on. Unless, that is, that it is actually a warning light relating to lack of LHM - a simple thing to check when on maximum height. The tank needs at least 5 litres in it to be sure to work everything.
With no brake light to worry about, now is the time to look elsewhere, starting with the slight possibility of a faulty main accumulator.
Based on the information contained in your postings, I cannot suggest otherwise at the moment.

No break warning light is pressure related. Rev up and it goes off. All spheres are new including accumulator. When it was slight loss of power steering I could be parking fine, touch brakes, light would come on and power steering would disappear, rev up and it came back. Now however no power steering at all.