Silly thought.

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Gibbo2286
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Re: Silly thought.

Post by Gibbo2286 » 30 Jul 2019, 09:30

Made a start on this yesterday, it's not going well, sun beating down on my back, rounded screw heads, clips that won't unclip, brittle plastic pipe snapped.

Now it's peeing down with rain and looks to be set in for the day :(

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Michel
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Re: Silly thought.

Post by Michel » 30 Jul 2019, 12:15

Gibbo2286 wrote:
30 Jul 2019, 09:30
Made a start on this yesterday, it's not going well, sun beating down on my back, rounded screw heads, clips that won't unclip, brittle plastic pipe snapped.


Sounds like a normal job on most Citroens..

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van ordinaire
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Re: Silly thought.

Post by van ordinaire » 30 Jul 2019, 19:17

That's cheered me up no end, I'll stop winging now about the huge lie that C15's are easy to work on.

Gibbo2286
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Re: Silly thought.

Post by Gibbo2286 » 31 Jul 2019, 08:36

Compared with this Van the C15 is a doddle. :) It's stopped raining now so off back out to finish the job in a few minutes, well after breakfast.

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van ordinaire
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Re: Silly thought.

Post by van ordinaire » 31 Jul 2019, 21:50

Well, of course, all things are comparative but no vehicle has defeated me as often as the C15 - although I'll concede the starter is easier than most.

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Re: Silly thought. Broke it!

Post by Gibbo2286 » 01 Aug 2019, 13:59

Got the thing all back together, fired it up, it ran for a couple of minutes then stopped and won't start again, eml is on and the diagnostics says 'pre-post heating sensor fault, not connected' . :shock: where the hell is it located.

Checked the glow plugs and they're all reading ok now and I'm sure everything that came off (connections) has been put back on.

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GiveMeABreak
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Re: Silly thought.

Post by GiveMeABreak » 01 Aug 2019, 15:11

Glow plug relay....

The relay is on the right shown as 1158

1158.PNG

Gibbo2286
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Re: Silly thought.

Post by Gibbo2286 » 01 Aug 2019, 16:29

Thanks Marc I found it hidden away under the damned BSI I might take it apart and see what's going on in there.,

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GiveMeABreak
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Re: Silly thought.

Post by GiveMeABreak » 01 Aug 2019, 21:38

It should be near the engine fuse box, usually off the left side, it won’t be in the BSI which is in the glovebox Eric.👍

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Re: Silly thought.

Post by Gibbo2286 » 02 Aug 2019, 10:14

So here it is and at Neil's request the old glow plugs the one with the blue mark is the only one that works.

Also the relay which I've opened to show the innards, can get the points to close by connecting direct to the coil but otherwise nothing, new one ordered so I hope that's a fix.
Attachments
GP4.JPG
GP3.JPG
GP2.JPG
GP1.JPG

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NewcastleFalcon
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Re: Silly thought.

Post by NewcastleFalcon » 02 Aug 2019, 11:41

Thanks Gibbo I like a picture or two. I may be following the same route myself with the Vectra, if my newly fitted glow plugs fail to spring into life. While glow plugs are not really needed for starting these days except in the most arctic of conditions, I do believe that the glow plugs could require to be operational in a regen, and a fault in the glow plugs/relay leg could stop the "computa" either initiating or completing a regen.

Maybe someone with greater knowledge of me on the C5 could confirm whether this is the case.

My little task on the Vectra has been to sort out an incompleted regen on the DPF. About to put it all back together after replacing the glow plugs and the downstream Exhaust Gas Temperature Sensor, giving the DPF the hose pipe treatment, and checking out the pipework to the pressure sensor.

Physically everything seems ok, but if one part of the sytem is not working then it blocks a regen of the DPF taking place. On the Vectra its as rudimentary as DPF systems go but whether the "computa" still has its knickers in a twist thinking that it is still stuck needing a regen even though it doesnt time will tell.

Regards Neil

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Re: Silly thought.

Post by Gibbo2286 » 02 Aug 2019, 11:49

I'm just hoping that the relay is a fix for the non-starting, not 100% sure. :(

I can't understand why it started first time after I put it back together then stopped after a couple of minutes.

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GiveMeABreak
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Re: Silly thought.

Post by GiveMeABreak » 02 Aug 2019, 12:37

NewcastleFalcon wrote:
02 Aug 2019, 11:41
....While glow plugs are not really needed for starting these days except in the most arctic of conditions, I do believe that the glow plugs could require to be operational in a regen, and a fault in the glow plugs/relay leg could stop the "computa" either initiating or completing a regen.

Maybe someone with greater knowledge of me on the C5 could confirm whether this is the case.

Regards Neil


The pre-heater plugs enable a rapid rise in temperature in the combustion chambers during the starting and cold-running phases.
The pre-heater plugs are also used for depollution, contributing to the reduction of nitrous oxides and soots.

There are 4 modes of use for the pre-heater plugs:
  • Pre-heating
  • Pre-heating under starter
  • Postheating
  • Postheating for regeneration
Although the Glow Plugs can be used in regeneration it is only at the request of the engine ECU if deemed necessary to load the engine - and then only for a short period (1 second max.). Whether they are activated or not in this case depends on the engine speed and fuel flow, otherwise there is a risk of knock / over heating. So they are not used as a matter of course - only if needed and briefly at that.

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NewcastleFalcon
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Re: Silly thought.

Post by NewcastleFalcon » 02 Aug 2019, 13:21

Thanks Marc,

So not part of a pre-regen "test" by the ECU to establish that all components potentially required for a successful regen are in order. If the circumstances arise that the ECU does make a call to the glow plugs during a regen, and they are not working, presumably it records some fault code, but the regen is not stopped.

REgards Neil

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GiveMeABreak
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Re: Silly thought.

Post by GiveMeABreak » 02 Aug 2019, 16:45

The ECU can employ various strategies to try and complete any failed regeneration attempt because of various reasons - but it can also activate the heated rear window to increase system load for example. These are most likely to be employed in the cases of shorter trips where the engine is not up to operating temperature or regeneration is constantly interrupted. If it can't regenerate using any of the strategies it will flag up the 'Risk of Clogging' warning to get you to go on a long enough drive to complete a regeneration.

Let's not forget that the fuel injection also plays a part in the post injection process to assist with emission control and DPF regeneration.