Xantia related (could be quite basic/obvious)

[Ratheram]

Well, the past I actually put some tlc into my xantia and well, got some great results.

Changed the spark plugs, had Bosch Super4's in there, ment to be better than standard long life plugs, did less than 20,000miles but fitted standard NGK plugs and what a difference. No hesitation now when I put my foot down and the MPG is so much better. That got me thinking. Ive owned the car for around 25,000miles, 2 years and never changed the fuel filter. Did that today. Yes, I should have done that ages ago. Often gets forgotten on servicing but the car revs smoother, idles better. Got rid of the airbag light fault, seat trigger 1 blahblah, you know the score and had a general tidy up and check through of the car. Got me wondering...

LHM. No history of it being changed, its more brown than green. Should I change it? Its not exactly like DOT4 brake fluid and gets water in the system.

Rear bump stops seem to be quite squashed into the floor, mangled and half missing. But are they actually important? Ok it stops the suspension arm hitting the body of the car but, is there more to it than that?

Gearbox oil? Its a manual but still, is there any urgancy to get it changed?

Got a fault on the ELIT (sure thats how its spelt, the old black citroen codreader) that is "mixture control regulation, permanent fault, lower limit exceded". I run without a catalystic converter, could it be because of that? Doesnt come up with any lambda sensor faults like what my old Xantia did when I ran it de-cat. The car runs fine, no light on the dash but I cant clear the fault

[Xaccers]

Haynes suggests 36K for fresh LHM with hydroflush used every other change.

[Citroenmad]

I would be changing the gearbox oil yes, even on a manual its a very good idea.

I would also be changing the LHM too, it should be a nice bright green colour. Change it and clean the LHm filters too, you might be surprised at the difference it can make to the car.

Bump stops only really protect fron the arm hitting the chassis so as long as they are there. I suspect they are a cheap thing to replace so you could do.

[CitroJim]

Rear bump stops seem to be quite squashed into the floor, mangled and half missing. But are they actually important? Ok it stops the suspension arm hitting the body of the car but, is there more to it than that?

They're vital to a good quiet ride. Rattiva's were like yours and she really bumped hard across speed humps. Replacing them made all the difference. I believe they also play a part in the rear suspension too as the car now rides better with new ones.

Gearbox oil? Its a manual but still, is there any urgancy to get it changed?

If there's no record of it being done, not a bad idea to do so. Remember, use only 75W/80 oil and nothing else.

Got a fault on the ELIT (sure thats how its spelt, the old black Citroën codreader) that is "mixture control regulation, permanent fault, lower limit exceded". I run without a catalystic converter, could it be because of that? Doesnt come up with any lambda sensor faults like what my old Xantia did when I ran it de-cat. The car runs fine, no light on the dash but I cant clear the fault

Magnetti-Marelli injection by any chance? Yes, seen it and it's a devil to sort out. It may well be your lambda playing up, the lambda heater playing up or the fuel pressure regulator regulating at too high a pressure.

The lambda sensor needs to run very hot to work properly and I'm wondering of the lack of back pressure with no cat is causing the sensor to run too cool. The sensor, if I recall, is a long way from the manifold and near where the cat is so if the cat is not there to hold back heat then there's a good chance the sensor is too cool. If so, get an exhaust place to weld in a new boss just below the manifold joint. Test the output and check it's nicely cycling between 0.2v and 0.8v a few times a minute. I'm not sure if the ELIT live data will show lambda output but the Lexia does. Else that, use a good quality multimeter to read the lambda sensor output directly. You must use a good one with a high internal resistance else the meter will excessively load the sensor and give a very inaccurate result.

[Mandrake]

Rear bump stops seem to be quite squashed into the floor, mangled and half missing. But are they actually important? Ok it stops the suspension arm hitting the body of the car but, is there more to it than that?

They're vital to a good quiet ride. Rattiva's were like yours and she really bumped hard across speed humps. Replacing them made all the difference. I believe they also play a part in the rear suspension too as the car now rides better with new ones.

The progressive lower bump stops on the rear arms are pretty important for ride quality, particularly on hydractive models. Why ?

The rear suspension is so soft on a hydractive model that even with the HA ECU's attempts to switch to hard mode during acceleration its very easy for the rear suspension to bottom with acceleration. Without the progressive bump stops the acceleration would temporarily bottom the suspension then as soon as you hit a bump WHAM, theres no suspension travel left to absorb it, so it hits the bump hard.

With the progressive bump stop in place the squat from acceleration will only push the suspension down far enough to just gently press against the uncompressed bump stop - leaving a good inch or more of useful suspension travel through the compression of the bump stop to absorb bumps.

Another factor is that if the suspension was allowed to completely bottom during acceleration the height corrector would make a large correction trying to correct for sustained acceleration, when you finished accelerating the suspension would go up and hit the top bump stop and stay there for a while (10 seconds or more) until the height corrector corrected it back down again.

With the progressive bump stop this still happens but to a much lesser degree as the acceleration induced squat is reduced, therefore the height corrector is making smaller corrections during driving, leading to less overall height variations/corrections thus better, more consistent ride quality.

(Maintaining consistent ride height is key to good ride quality - thus problems like sticky height corrector linkages causing poor height regulation will also cause inconsistent poor ride quality...)

The progressive bump stop is a bit of a kludge really but an important and necessary one!

[Jabo]

What should a healthy bump stop look like?

[Ratheram]

Mhmm, very interesting replies there. Think ill get onto doing the fluid change and gearbox oil change soonish.

But the bumpstops, I really dont notice the car dive like you talk about and Ild say mine do look knackered. Ive recently had new rear spheres fitted and yeah, I have to say, cornering speeds now are around 5-10mph slower as the back seems to sit lower on corners because of body roll/weight transfer and the inside wheel tends to want to lift that isnt a very pleasant experiance. I couldnt say my ride is harsh, I know my rear height corrector works fine as that gets greased up monthly but bottoming out, never on acceleration.

[Ratheram]

Also, another little thing that catches me out now and again. If my car gets hot and bothered from a motorway drive or a spirited drive, drive round slowly for a bit to cool it down before I park it up for the night.

The next day I go and start my car... Nothing.

Ild hold the key round in the start position for 20seconds+ then it would suddenly kick into life and start fine. Ive hit the starter with a hammer befire (old AA trick) but nothing. Nothing is engauging or spinning. Ive got a new battery, new earth wires, the live wires arent getting hot when I try and start it so, I can only put it down to heatsoak. Is there a way of combatting it if that is the problem?