Just a few more Xantia problems.....

[Stepto1]

Now I've sorted out all the obvious problems, I've noticed a few more subtle problems on my 110 HDI.

When I start it up after a few days, the back sinks to its very lowest setting, then rises back up to its normal position. This to be fair, is about an inch higher then it should be.

When changing gear and putting my foot down, there is an audible clunk or bang from the engine compartment. Engine mounts?

When the engine is under load and at higher revs the turbo is starting to whistle. Is this normal? She's done 145k miles.

Many thanks.

[Sulla]

Now I've sorted out all the obvious problems, I've noticed a few more subtle problems on my 110 HDI.

When I start it up after a few days, the back sinks to its very lowest setting, then rises back up to its normal position. This to be fair, is about an inch higher then it should be.

When changing gear and putting my foot down, there is an audible clunk or bang from the engine compartment. Engine mounts?

When the engine is under load and at higher revs the turbo is starting to whistle. Is this normal? She's done 145k miles.

Many thanks.

Regarding the sinking, mine also does this and always has done. Mine also had the clunking sound when changing gear, first time it was a spacer on the exhaust, second time was engine mounts.

Never had a whine on the turbo at high revs though.

[Peter.N.]

Probably sticky height corrector valves for the first problem, the second yes very likely engine mountings, look at the top one while blipping the throttle and see how much it moves.

Turbo whistle is variable and very much subjective, any increase though could be due to a leak in the air ducting.

Peter

[Peter.N.]

Sorry, I will have to learn to type faster

[Stepto1]

Well, two out of three isn't bad! I'll have a look at the exhaust although I think it's ok. Engine mounts are my guess.

It's just a whistle or whine when pushed hard. Oil is top notch.

I figured they'd be a problem. I've not had a warning light on the dash for a while now!

[Stepto1]

She is VERY overdue an LHM change/flush.

[citroenxm]

Ill tell you exactley whats happening...

When you stop the car your anti sink valves ARE working and locking the struts out and keeping the car up... however, the system between the regulator and anti sink valves are loosing pressure on the return which means when you start the car and the anti sink valves open up on feed pressure up to pressure, the system sinks to compnsate for the returnd fluid after the anti sink vales... so its actually NOTHING to do with sticking height correctors or linkages...

Over due LHM will contribute to this...

As for the knock, if you follow the top engine mount at the cam belt side theres an extra mount that goes back towards the back of the engine bay... theres a rubber mount in here which breaks with engine rock under load.. The part is available and was not expensive last time I got one.. they were about 30 quid... Its held on by three 16mm bolts and a 4th through the forward section.. Its only fitted to HDi 110 setups and not to 90bhp...

Paul

[Stepto1]

Citroenxm, you're a genius. That makes perfect sense to me. Flush with hydrocage and replace LHM?

I'll have a look at the mounts. The ones I saw looked good but the one you described sounds hidden?

[Xaccers]

Sinking on start up can be due to spheres at the back being low.
They have enough pressure to close the anti sink valves but not enough to keep the back up when the anti sink valves first open.
It can also cause the car to sink when you get out.

[Stepto1]

Now I'm confused! Lol! I've got some new spheres to go on.

[citroenxm]

Citroenxm, you're a genius. That makes perfect sense to me. Flush with hydrocage and replace LHM?

I'll have a look at the mounts. The ones I saw looked good but the one you described sounds hidden?

im not a genius... but thanks for saying so....

the top mount is not hidden that much.. look between the cam belt cover and side of the suspension turret... its down there.. opposite the rocker cover...

[Xaccers]

Now I'm confused! Lol! I've got some new spheres to go on.

The anti sink valves are shuttle valves.
The main system pressure keeps them open, and the sphere pressure keeps them shut when the engine is off.
If the spheres are weak the valves don't shut properly or when they open the pressure drops so the back drops until the pressure builds up.

[Stepto1]

Got you. Makes sense. I'll get the new spheres on and then flush the system.

[Stepto1]

Which bush would have gone if the engine is rocking back and fourth?
Pic from eBay.

[RichardW]

Nothing on that picture There's a link that goes from the bush at the top right to the inner wing - it is the bush in this link that breaks up.

The most likely cause of the rear sinking is the anti sink sphere (which isn't at all!) being flat, much as described by Paul.

Mine has developed a turbo whine too. Check the the short rubber hose that connects the turbo to the pipe under the engine - this can split - or the clamps can be loose. Mine was much improved by changing the oil, and tightening the clamps on that hose.