My 1995 Xantia 1.9TD LX seems to eat glowplugs. It starts to splutter and cough every 3-4 months or so on cold starts, which is only cured by replacing the glowplugs.
Is this lifespan normal? Seems to be regardless of plug quality (NGK, Beru, champion, etc).
Have checked the voltage across the plugs, and the relay is definitely switching on and off ok.
Additional stupid question: I have a multimeter, which parts of the plug do I put the contacts on to test the plug? (The resistance seems to bounce all over the place when I try and test them).
Only bonus is that I am now a master at changing the darn things!
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Duff injectors?
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Not normal then, no?
guessing injectors don't all go at the same time, so if its the same plug failing every time I can identify the dud injector, yeah?
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Hi Xantiargh!,
When you take the glow plugs out, do you see any physical damage on any of them?
How do you diagnose that the glow plugs need changing?
Measuring the current draw for each glow plug in turn (without the common bus-bar connected) would be the best way to identify one failing plug.
The reason I suggest injectors is that if you get a poor spray pattern, the diesel knock in that cylinder can become more severe, which can damage the (comparitively) delicate glow plug.
If you can't find any other faults, particularly in the glow plug electrical supply, and you do find it is the same cylinder every time, I would recommend getting the injectors checked for blow off pressure, and spray pattern. Any good diesel specialist should be able to do this.
number_cruncher
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Daft question perhaps, but are you sure you're using the correct glow plugs?
Many cars nowadays use reduced voltage glow plugs, and if you've fitted these and your relay pumps 12 volts they won't last very long.
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Use your multimeter to test the resistance of each plug between the central nut and the plug body - you must remove the plug or disconnect the plug lead for this to work, otherwise the other plugs will interfere with the reading. The plug's resistance should be between 0.5 to 1 ohm (and definitely not zero). That's very small so you need very clean contacts.
If you are tempted to measure current instead of resistance, remember the plugs could draw up to 30 amps each!
If you are brave enough, you can connect the plugs to a battery away from the car and see how long they take to glow red hot and whether all the plugs glow in the same way (mainly at the tip).
Plugs probably won't show visible wear even after 100,000 miles, though may suffer random electrical failure before that - that's not meant to be a reliable estimate of plug life, just an indication that they are supposed to last a lot longer than yours do.
Ian
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Just checked my old maintenance notes - my XUD glowplugs (306 XRDT) actually have a resistance of 0.4 ohms.
Ian
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Maybe you are being sold plugs (V) type which are for older models without post heating? I think your car keeps the plugs glowing for a while after starting to reduce emmissions and clatter, and maybe the plugs they give you are for earlier models which don't have this. The later plugs have a regulator in them to stop overheating. (N) type.
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Hi all
Many thanks for the replies.
If more info helps, the car has allegedly done 117k, (from 91k on with me). Based on the service history it sat around for a couple of years not moving much (low mileage, couple of thou a year, tyres cracked). The radiator has been replaced at some point cos it?s very shiny). Rarely belches smoke, returns @ 38mpg. Regular oil/misc filter changes...
Number_Cruncher:
I change the plugs cos after a couple of months after new plugs the car begins to struggle to rev when first started from cold, and emits white smoke. This will get progressively embarrassing to the point where I can't see my house after starting the car on the driveway (slight exaggeration!) and so I change the plugs. After changing the plugs all is tickety-boo for a couple of months before it starts chugging again.
When the glowplugs are removed I can't see any evidence of pitting or scarring, they're just very sooty; but I figure that?s normal(?).
Railroad:
I've tried several brands and suppliers, including two Citroen specialists. I'm sure the law of averages means I must have found a supplier who gave me the right plugs once! But then again, maybe not :)
IanT
When I last changed the glowplugs I kept them and got a multimeter. However when I try and measure the resistance on a 10 ohm scale it doesn't ever seem to settle down, sometimes it will pause at sub-1 ohm, then it will shoot out of range and back. If I get it to settle for any length of time sub-1 ohm does that mean the plug is ok, or if its dud will it always be out of range (infinite resistance)?
Perhaps I should check on a lower setting, 1 ohm?
Sooty Tailpipes
Ah, didn't know there were different types. I'm going to buy some new plugs soon so will badger the parts dept about them to see what type they're giving me...
Thanks again..
Mike
PS. Apologies for waffle...
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Hi Mike,
Like your user name :-)
This is a bit of a shot in the dark, and I hope to eleicit the wisdom of some back roomers who know more about these engines than I. I am assuming the white smoke is unburnt fuel as opposed to steam - does it use any water? On the basis of that assumption...
I think it is possible that you aren't getting enough compression. i.e., if you have marginal compression and good heater plugs, you have enough to start and run. As the heater plugs become less effective, you get less total heat in the pre-combustion chamber, so there is just enough heat + compression to start, but there isn't enough total heat to maintain smooth combustion when your heater plugs switch off or switch to reduced power.
Obviously, a compression check will tell you one way or the other.
Other back roomers - please attack this hypothesis - it isn't based on experience - it is only a guess.
number_cruncher
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I'd say there has to be some combustion fault - even on a diet of short runs I would expect >45mpg ?
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I would suggest the combination of poor mpg (like Andrew I would expect>40) and the difficulty when cold = a problem with the fuelling system plus sooted up plugs.
With those miles I have two guesses:
1. worn injectors
or 2. cold start mechanism not disengaging propeerly giving a permanently rich mixture.
I would say 1>
madf
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I run a non-turbo 309, which I believe is the same basic engine, but with slightly different inlet & exhaust manifolds.
I don't think there is an enrichment device, and cold starting relies on the glow plugs and a temperature controlled slight increase in idling speed.
First I would check the plugs really are U/s. I found the easiest way was to use a high discharge battery tester as if it were a jump lead, to test the plugs after removing them (Snap-on one, with the meter attached to a lead and operated with a button). Gripping the plug where the nut is, and touching the terminal end against a good earth like the camcover, with the other end of the test attached to the live terminal of the battery. Using the battery tester meant I could get a good connection on the camcover before pressing the button to supply the current, and I could also monitor the voltage drop.
You can watch the plug get red hot within 3-4 seconds, and it was really quite easy to compare them. BEWARE THEY GET VERY HOT!
309 plugs 166K with no trouble, 2 Fiat Punto diesel glowplugs faulty at 81K.
Have you checked the valve clearances? Tend to close up circa 100K, giving poor starting & low fuel consumption. Easy to do, but adjusting a bit more hassle
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Not an expert but two things come to mind:
1. There is a cold start(?) cable that goes to top of the (Bosch?)fuel pump. If I remember correctly it should be tense when engine cold and slacken off when engine warms (I think)
2. What about the relay (little blue box inside near side wing) which times the glow plugs. If you open the bonnet you can hear it click on, light goes out after about 7 seconds, start engine and it should "click off" after a few more seconds, if not it may be staying on and burning out the glow plugs?
Beru are reckoned to be the best plugs for these engines and you have tried those, but mine always lasted for years.
If you don't get an answer which solves the problem here try specialist Citroen board at:-
www.andyspares.com/discussionforum/forum.asp?FORUM...3
or
www.citroenz.com/forum/
Someone will give you the answer!
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Would suggest that the injectors need attention as others have said. My 306 TD made clouds of white smoke on start up until i had the injectors done, all were low blow off pressure and spraying 'streaky' and not atomising properly according to the place that did them.
38 mpg does seem a bit low, my 306 struggled to better 40 mpg before the injectors were serviced, estimate it's averaging 45 mpg now.
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I wasn't meaning to disregard the possibility that the trouble may be faulty injector(s, particularly at this mileage. I had the 309's done at 110K as a precaution by a local specialist(Nothing seriously wrong, apart from one having a slightly incorrect jet), but one of the previous posts had established that there were no obvious signs on the glowplugs except soot.
Better to eliminate the no cost alternatives before changing the injectors (plus the washers under the injector body and the one under the tip)
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Its been a while (couple of months) since I last had my head under the bonnet, so I haven't checked the waxstat recently, however the revs do drop off as the engine warms up so I reckon its ok.
I checked the relay last time I changed the plugs, using a multimeter to watch the voltage over the plugs. Seemed to work ok.
Valve clearances are probably beyond me, though I have a Haynes manual and a feeler gauge. I'll have a read up and see if I reckon I'm up to it.
On the basis that its a good idea to get either a compression test, or injectors serviced, what sort of ballpark are we talking cost wise?
Also, can anyone recommend a diesel specialist thats near Peterborough and preferably open weekends (I work in London so weekdays are not good).
Thanks again for the advice folks, much appreciated...
Mike
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Are you sure the glow plug are timing out and going off. Regards Peter
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"Also, can anyone recommend a diesel specialist thats near Peterborough and preferably open weekends (I work in London so weekdays are not good)."
Have you tried
www.pleiades.uk.com/home.html
I know that they are hydraulic specialists but their website also says
"We also service and repair Citroën vehicles in our workshop."
They are in Sawtry
I know it's some way from Peterborough (40 mins?) but I can also recommend
Eurocars, in Loughborough, tel 01509 264271 - they are Cit trained mechanics and very helpful and are also open all day on Sats. They may even suggest the solution over the phone they are that helpful!!
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