V6 questions

[Old-Guy]

I've spent several hours this evening trying to find answers to a couple of simple questions without success:

Hydraulic pumps; I've a fair bit of experience of humble (non-V6) Xantia hydraulics, but I understand that (some) V6 XMs have separate steering and suspension pumps rather than dual pumps (like S1 Xantias). Is this just ES V6s? All V6s? All (S2) XMs?

Is it just the PRV (ZPJ4 24V) V6 that have a reputation for fragility? i.e. if you're going to buy a V6 make sure it's a PSA ES 9J4?

I'm really after a 2.1TD Break, but if a nice solid late V6 Break appeared, I might be tempted now given that I don't do big mileages any more.

P.S. (the brain really has turned to jelly) - I started out to find what is the realistic life (miles and years) for an ES 9J4 cam belt?

Changing the 11 year-old cam belt on our 1.9TD Xantia was the first major task after getting it home - well overdue!

[xantia_v6]

In no particular order...

The ES9 timing belt is rated for 60,000 miles or 10 years, but it is a strong belt and failure is rare even of those limits are exceeded by some margin. Changing it is not an awful job, but can be a bit daunting the first time (I must have done about 10 by now).

There are 3 general families of pump, those for sinkers, those for anti-sink and that for ES9. Within the first 2 groups there are several variants of pulley (and mounting?) depending on engine type. Sinkers have single-outlet 7 piston pumps, andti-sink cars have 6+2 dual outlet pumps.

[Old-Guy]

Thanks for the quick reply. This now brings me to the issue of identifying the various V6s (in XMs) with certainty; it seems that some XMs stood unregistered for than some Xantias did, particularly existing stock unsold when Citroen UK announced an upgrade of specifications (in another bid to boost sales); with the result that I think I have worked out which is which of the two PRV engines, but I'm not certain.

Trawling through umpteen old XM photos, I've selected 3 photos of (what appear to be) the three different V6 engines. Have I identified them correctly?

PRV 12V ZPJ (XM S1 1989–1997)

XM_V6_PRV_12V_tmb.jpg

PRV 24V ZPJ4 (S1 & S2 XM 1993-1997) (exhaust cam & follower wear problem?)

XM_V6_PRV_24V_tmb.jpg

PSA 24V ES9 J4 (S2 XM 1997-2000)

XM_V6_PSA_ES9J4_tmb.jpg

"Time spent in reconnaissance is seldom wasted."

[Dieselman]

Your deductions are correct, apart from the Prv engine in both forms ran until 1997 then was replaced by the Es9j in 1997 model year.
The Prv-24 only suffered valve train wear until modified in February 1992.
All unmodified Prv-24 chewed themselves to bits a long time ago, nearly all were replaced under warranty.
If you come across a Prv-24 for sale you wont be confusing it and can be certain the seller will be telling you exactly what it is.
Prv-12 valve can be either manual, or auto gearbox, Prv-24 are all manual, all Es9j are auto in the Uk, but could be either in other markets.

[xantia_v6]

Unless you particularly want a series 1 car, or manual transmission or a break, I would suggest that the ES9 is the best V6, particularly for fuel economy.

[Old-Guy]

Thank you both. Ideally I'd like a 2.1TD (either Bosch or Lucas) as being both economical and easy to fix, but V6 Exclusives seem to generally have been better looked after - I'd like a Break but they are like hen's teeth - so a I might be tempted by a V6.

Now I understand why I was confused with the PRV engines, somewhere I read that the PRV 24V replaced the 12V.

[Old-Guy]

I'm seriously tempted by a late-ish V6. The advert says that the "auto box inhibitor relay" has been "by-passed" as it had an intermittent fault. He also believes that this is why the cruise control has never worked. As far as I'm concerned, this relay is a safety-related item!

So:-
1) Is this relay (relatively) rare rather than just somewhat obsolete? I have a complete collection of salvaged Xantia relays.
2) Is this a common fault?
3) Can I reasonably expect cruise control to work if the relay is replaced?

There are a few other minor issues, such as central locking on OSR door does work - (there's a surprise. Just like Xantias!). Remove door card, lubricate and bend the actuating rod so it doesn't stick?

Sorry to be asking simple questions, but I may not have time to research the relay issue

Thanks in advance.

I'm going to check it over in a couple of days - I'll let you know how I get on.

[xantia_v6]

The starter inhibit relay is just a standard Bosch-style 5 pin relay. It is linked to the cruise control (so that cruise disengages if you select neutral). It is probable that the root cause of the starter inhibit failure is the multi-function switch on the 4HP20 transmission, they are somewhat under-engineered and I have had a couple fail on Xantias. They are easy to change but probably hard to find now, but were used on several makes of car. Maybe that switch just needs adjusting.

The most common problem with Cruise on an XM is dirty contacts in the brake pedal switch, they usually need to be cleaned every few years, although sometimes the brake light contacts overheat, causing the plastic to deform and failure of the cruise circuit. XMs don't suffer the splitting of the hose where it attaches to the vacuum pump (very common on Xantias) because the correct diameter hose was fitted at the factory. Other failure modes are possible, especially if someone has been playing with the system attempting to fix it.

[Dieselman]

I wouldn't worry about anything electrical on an Xm, they are simple and we have the circuit diagrams. See post viewtopic.php?f=13&t=7592&start=110#p124757
The starter inhibit relay is a standard five pin relay and does interface with the CC relay.

Condition is everything with an Xm, Afaik, that car has no rust, but thoroughly check the jacking points, inner sills at the rear, the rear chassis rails where the rear subframe mount is, the front wheel-house rear end. Pull the trailing edge of the front bumpers out to check the mounting outriggers are not corroded.
You are aware of the HP20 service life issue, due to lack of being able to access the filter.
That one has had a stainless steel exhaust recently.

Make sure the spheres are in good condition. Run the engine and bounce each end of the car up and down vigorously, which should reveal it is very floaty, then switch off with the doors closed and wait at least 30s, until you hear a clunk, then bounce again. The suspension should be very much stiffer on the second bounce test.

My preference would to have not had cross climate tyres and have Michelin Primacy. CC tyres are less dry weather grippy and will wear faster. Unless driving in Arctic conditions, Xm don't need winter tyres due to the supple suspension allowing the wheels to ride up onto packed snow.

From the images posted it appears to be riding a little high at the front, which indicates it might need adjustment. When idling, sighting down the brightwork should lead to a line just intersecting the top of the wheel rim. The car appears about 25mm too high at the front.
This is a common issue on Xm that have sat around for long periods, as the height corrector spring rod deforms a little, unless the suspension is set to Low.

The slight press mark in the right rear door is due to something having pressed the skin in, but there is a stiffening plate mounted there, which causes the panel to distort. It would be difficult to PDR that dent as the stiffening plate resists deformation well.
That plate is what makes the rear doors close with a luxurious thud, rather than a clang.

I saw that car briefly a couple of years ago and it would probably be my choice of the 3 litres for sale at the moment given it's in Mauritius blue with almond leather, which is a rare option and really lifts the interior colouring.

Xantia_v6 will be your best adviser regarding the Es9j engine and Lexia diagnostics, but in reality, there's nothing you can't fix yourself on an Xm. I suspect that one hasn't had the timing belt done recently.

[Old-Guy]

Gentlemen, thank you both for your comprehensive answers. I apologise for asking yet more questions:

The claimed 58k is supported by the on-line MoT history which goes back to 2006 (at that time 29k in 7 years = 4k p.a.)

Service parts availability, now and in the future?

HP20: My understanding is that the filter can only be changed by removing and partially dismantling the gearbox.
Shouldn't be a problem at 58k?
Changing the ATF: Normal service item? DIY?

Ride height:
Do XMs have the same height control design as Xantias with plastic 'dog-bone' link to a clamp on the ARBs?
I have a suspicion that the seller may have been in the habit of driving in Intermediate instead of Normal - if so, would you be inclined to walk away?

Cam belt: should have been done in 2009 and 2019 under the first 'no-expense-spared' private ownership; I'll check historic invoices for belt and water-pump.

Thermostat: rarely get changed until there's a problem, then it's too late. In my experience they slowly age like cambelts; a combination of miles and years; they need to be changed at the same time as cam belts - at trivial extra cost.

Is the ES9J's cooling circuit difficult to bleed?

Water-pump: should be O.K. despite the age? Change at next belt change?