2.0HDI hunting at idle

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dave_xsara
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Re: 2.0HDI hunting at idle

Post by dave_xsara » 08 Jul 2019, 10:07

Has anyone had the fuel gauge intermittently dropping the signal and flashing the orange light - then a few minutes later returning to correct tank level?

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GiveMeABreak
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Re: 2.0HDI hunting at idle

Post by GiveMeABreak » 08 Jul 2019, 11:49

Probably a sticking contact wire on the sender

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Re: 2.0HDI hunting at idle

Post by dave_xsara » 08 Jul 2019, 12:19

Grand - I'll give it a clean over the 12th.

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Re: 2.0HDI hunting at idle

Post by GiveMeABreak » 08 Jul 2019, 13:02

See my post here for a picture example - you have a pump and sender on your car, but the one in the post link below with pics is a sender only - no pump, but still gives you an indication of where the wire can become detached giving erratic readings...

viewtopic.php?f=53&t=62630&hilit=sender#p609032

So bear in mind it's not the same unit as yours.

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Re: 2.0HDI hunting at idle

Post by dave_xsara » 17 Aug 2019, 21:38

Only getting around to this now. The wire looks okay. Should I just resolder it to ensure the contract is correct? The tracks for the potentiometer look to be well worn, could they actually be the problem?

Also what is this filter at the bottom and should this gum be covering it partially?
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myglaren
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Re: 2.0HDI hunting at idle

Post by myglaren » 17 Aug 2019, 22:19

That looks suspiciously like the gloop that grows in diesel.

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Re: 2.0HDI hunting at idle

Post by dave_xsara » 17 Aug 2019, 22:28

What is that thing anyway?

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GiveMeABreak
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Re: 2.0HDI hunting at idle

Post by GiveMeABreak » 18 Aug 2019, 00:07

Can't speak for 'the blob' and I have no electrical diagram for the system on this vehicle, but the track does look worn and if it's not making good contact, then obviously readings will be erratic.

Part number for the pump with gauge is 1525T4 £59 inc postage for a new VDO one:

https://www.ebay.co.uk/p/VDO-CITROEN-XS ... 2043718202

dave_xsara
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Re: 2.0HDI hunting at idle

Post by dave_xsara » 18 Aug 2019, 10:20

I'm guessing that it is the inlet for the pump as there is no other inlet on the bottom.

To repair the tracks I think I'll get a PCB trace repair pen and fix it that way.
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Re: 2.0HDI hunting at idle

Post by dave_xsara » 18 Aug 2019, 13:18

Repaired the track with solder. Readings from the gauge now correct again.
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Re: 2.0HDI hunting at idle

Post by GiveMeABreak » 18 Aug 2019, 13:22

Well done, I hope the solder is flat and smooth or it may wear the contactor, - but at least the pumps are not expensive to replace if needed.

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Re: 2.0HDI hunting at idle

Post by dave_xsara » 18 Aug 2019, 13:45

Yeah it's smooth, but I'll go over it with some wet and dry before installing.

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Re: 2.0HDI hunting at idle

Post by dave_xsara » 18 Aug 2019, 22:29

Is there any special additive that I can add to the tank to dissolve that gunk? I'm sure there will be more of that crap in the tank so rather than it clogging the filter again I'd try to get rid of it now.

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myglaren
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Re: 2.0HDI hunting at idle

Post by myglaren » 19 Aug 2019, 10:02

There's a description of the problem here

A video



Apologies for yankspeak.

A treatment, never had any experience nor need for this

It has come up here in the past. Ideally the tank needs to come out and be washed out but depending on how bad it is it might be possible to avoid that.

I could be fooling myself but I always run the tank practically empty then brim it rather than putting a few quids worth in here and there.

If you still have the blob, try chucking it into some meths and see if it breaks it up. Could be that a dose of meths in a practically empty tank, left for a day or two then filled with fresh diesel to dilute the meths might work - speculative though.

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myglaren
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Re: 2.0HDI hunting at idle

Post by myglaren » 19 Aug 2019, 10:11

You should be able to buy the chemicals at a ships chandlers or boating supply shop if you are inland.