C4 Diesel Adblue Tank

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GiveMeABreak
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Re: C4 Diesel Adblue Tank

Post by GiveMeABreak »

Not legally. These cars are certificated for public road use only because they meet or exceed the relevant emissions standards / legislation.

However, like most things this newer SCR technology, use under 'real world conditions' can't really be simulated properly in the lab. Things like longevity and time-related impacts on components are very difficult to simulate. The SCR system is a good idea and a relatively cheap and efficient way to eliminate most of the NOx produced by a diesel, combined with 99.9% of the particulate matter trapped by the DPF.

With regard to the Adblue systems, the earlier systems had teething problems - the tanks for example had a lot of metal components inside which over time, were adversely affected by the UREA solution causing corrosion and blockages. So the newer tanks were changed to incorporate more plastic components to prevent this. A lot of these tanks were replaced under warranty within the 3 years / 60k miles or equivalent, but in a lot of cases, PSA made some varying contribution to replacing these when they were out of warranty depending if the car had been serviced properly of course. So that is an example of where they have improved these.

Another was the unvented cap - which could hinder the pump from working correctly and cause it to break down - requiring a complete tank replacement because of the reasons already mentioned. A vented cap was introduced on affected models to solve that.

Then there was the issue of the NOx sensor harness wiring getting cut / burned through leading to the engine thinking the Adblue tank was empty and preventing engine starting.

At some point we won't be worrying about all this when they electrify us all - we'll just start wrecking other areas of the planet to make all the batteries needed instead :roll:

joecrow
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Re: C4 Diesel Adblue Tank

Post by joecrow »

I have had further conversations with my local Citroen dealer, mentioning the "Guided Support", and they are going to carry out a diagnostic test and perhaps will pay some or all of the cost of putting it right. It helps that I have full service hiistory for the car, and it is just less than 5 years old, with 27000 miles on the clock. Its going in on 04/03, so I will report back next week.

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GiveMeABreak
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Re: C4 Diesel Adblue Tank

Post by GiveMeABreak »

Best of luck with it and yes, please let us know the outcome.

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Paul-R
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Re: C4 Diesel Adblue Tank

Post by Paul-R »

The guided support for vehicles apparently pays for the cost of the tank and you pay the labour. This is a very rare case of the cost of the labour being less the cost of the part - or at least for our 308. The labour for ours is/was £70 (including VAT).

mashbury
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Re: C4 Diesel Adblue Tank

Post by mashbury »

I've had this wretched AdBlue tank problem as well. Symptom was (having just set off on holiday to Cornwall) it complained of an emissions fault, then a few miles later announced that the car would not be allowed to start after 600 more miles!. So, about turn and take another car. Not happy. Then later, driving it about, the fault disappeared..then, a few journeys later it appeared again...etc.

Dealer diagnosed the tank and yes, £1200 to change! The car was just over 5 years old, otherwise, the dealer told me, CItroen would have provided the part FOC. I complained to Citroen UK with some logical arguments - not least how come they changed the cap on this tank under a recall if there were not some serious underlying problem? As `givemeabreak' says, the pump trying to suck in a plastic tank puts strain on the electronics.

Anyway, after a LOT of phone calls and ping-ponging between Citroen UK and dealer in the end I lost the will and settled for 50% discount (on parts and labour)..a mere £600. They try to grind you down...and it works!

They mentioned an `abacus' (!?) which seems to be their goodwill (so-called!) calculator..this may be the same as the `guided support' mentioned.

I don't know for a fact but I believe the new tank (electronics) have to be coded in to the car so that is a potential problem if you try sourcing your own tank (dunno if it can be done via Diagbox). There is definitely a (different?) noise coming from the tank now for a few seconds having switched off the car so something has been changed.

So, if you are within 5yrs old (and less than I think 75000 miles), press for labour charge only, if not, press for a substantial rebate.

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Paul-R
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Re: C4 Diesel Adblue Tank

Post by Paul-R »

mashbury wrote:
27 Feb 2021, 23:38
I don't know for a fact but I believe the new tank (electronics) have to be coded in to the car so that is a potential problem if you try sourcing your own tank (dunno if it can be done via Diagbox).
That's correct - at least for our 308. The tank currently supplied is a supersession part number and requires coding in. A Diagbox is used but it has to be a dealer's Diagbox as it requires a connection to the PSA servers in Paris. At least, that's what I was told.