xantia starting problem

lostinlincs · Post by **lostinlincs** » 27 Nov 2004, 22:09

95N xantia TD
Ah you have probably heard it before but....
Started as an intermittant problem. On turning the key to start, the pre heater light would not come on, engine would turn over but not start. Rectification initially involved hitting the glowplug relay with something hard and that "appeared" to do the trick.
However two weeks later and the problem has mannifested itself again. Thought i could hear the relay clicking when i tried to start it however - changed the glowplug relay with one from a breaker - valeo instead of bosch previously fitted(will that make any difference?) Old relay had evidence of corrosion and blackening on one of the contacts.
Alas as darkness fell the car was no better.
Can i take the relay out of the circuit to check the integrity of the rest of the start circuit?
Car ran and started normally before this problem.
Any top tips?

AndersDK · Post by **AndersDK** » 27 Nov 2004, 22:22

Any records on the glowplugs ?
They do have a finite service life - some 65Kmiles (100Kkm).
To test the glowplugs, you must unscrew the small nut holding the cable, then measure the ohmic resistance from tip to earth is less than 1 ohm. (try shorting out your test leads first to get a reference reading).
The glowplugs are timed on longer than your glow light indicates meaning you can turn the key, then check you have a voltage at the plug end of at least 10.5V.
Also check your battery voltage ! Should be at least 12.4V directly over the poles when the plugs are timed.
Many a battery at end of service life has caused endless troubles for diesel owners.

lostinlincs · Post by **lostinlincs** » 27 Nov 2004, 22:49

battery is fairly new
If it's a dodgy glowplug, will it prevent the pre hteater amber light come on on the dasboard?

AndersDK · Post by **AndersDK** » 27 Nov 2004, 23:02

I know from the BX19D that the timer unit has some means of checking the plug current, as the current passes thru a high power lo-ohmic resistor inside the unit.
Could well be bad plugs not consuming the required current for pre-heating causing the light to miss.
I'd say you start checking the voltage at the plugs when timed - and then take it from there.

lostinlincs · Post by **lostinlincs** » 27 Nov 2004, 23:44

Thanks
Anything else to check?
I read somewhere about the battery tray -is that worth a look in this case?
Percussion adjustment of the relay previously worked -was that a red herring/concidence?[V]

lostinlincs · Post by **lostinlincs** » 28 Nov 2004, 19:34

Unfortunately i have no multimeter/tester.
Jury rigged the previous relay and get a click on and click off approx 15-20 secs later -again with no light. does this mean the plugs are the likliest cause? Plugs have been fitted for at least 45k miles as I picked the car up with 64k on the clock. Its just if I have to get close enough to test them properly I may as well replace on spec.
On that subject are the beru ones the best replacement?(95 TD 109k)
Oh on looking closely at the battery tray, its pretty corroded - would that cause any problems here?
Thanks all

oilyspanner · Post by **oilyspanner** » 28 Nov 2004, 19:56

You can always prove the glowplugs work by connecting em up to battery positive using something like a jump lead and counting to ten before cranking the starter, be careful not to cause a short circuit, if it starts then the problem lies elsewhere.
Stewart

lostinlincs · Post by **lostinlincs** » 28 Nov 2004, 20:19

Ok without trying to sound like a complete dullard and before i add to my problems....- is the battery wired up to the rest of the car whilst attempting to heat plugs, any plug/all plugs ?[:0]

PowerLee · Post by **PowerLee** » 28 Nov 2004, 20:23

Hi
The NEGATIVE terminal of the battery is connected to the bodyshell & engine / gearbox.

oilyspanner · Post by **oilyspanner** » 28 Nov 2004, 20:24

Yes, all it does is provides 12volts direct to the glowplugs, missing out relay etc, careful though, just apply current to one of the terminals on top of the glowplug, current will get to the rest and it should go, I repeat the warning about shorting though, careful not to touch anything else with your "Hot" wire.
Stewart

lostinlincs · Post by **lostinlincs** » 28 Nov 2004, 22:39

ok
On trying to attach to plug - neg terminal car body and pos on plug-could you clarify where terminal part of plug is? have the hex top with metal tube pipe and the lower part which more rusty in colour where the (i assume)pre heating electrical lead runs. Where best to pop the leads? em earlier experimentation resultined in some slightly disconcerting sparks[:0][:I]
Also is it best to have battery disconnected from the rest of the car while doing this?

oilyspanner · Post by **oilyspanner** » 28 Nov 2004, 22:45

No Battery positive terminal connects to positive terminal on glowplug (nut on top) otherwise battery is as normal, leave connected for ten seconds then try starter, if it fires normally then its the relay cos you have just done its job for it. the sparks can be disconcerting, arent you glad its a diesel engine;) recomment you make a lead up, connect to glowplug terminal leaving existing connections there and then touch other end to battery positive terminal, use some fairly chunky cable as the plugs draw a lot of current, you can then break circuit instantly, hope this helps

lostinlincs · Post by **lostinlincs** » 29 Nov 2004, 01:01

Much thanks
Watch for the mushroom cloud over this way in the morning[:D]

lostinlincs · Post by **lostinlincs** » 29 Nov 2004, 01:16

oh just further pain saving postnote
i take it the neg terminal is not req'd or is it?

nick · Post by **nick** » 29 Nov 2004, 01:24

No, the metal body of the glowplugs (along with practically everything metal on the car) is already connected to the negative terminal on the battery. You just need to connect 1 wire from the battery positive terminal to the terminal on top of one of the glowplugs.