C4 Diesel Adblue Tank

[citroen since 1973]

Follow Up - Hi everyone. It’s been 15 months and a further 15,800 miles since I asked for advice about, the dreaded, AdBlue warning light appearing on my 2018 2l C4 Grand Spacetourer (page 2 & 3 of this thread). After my local Citroen dealer (who had never heard of any problems with faulty AdBlue tanks) found no issues and carried out a denox system reset, my car has performed perfectly.
However, whilst travelling down the M6 yesterday, the same error warnings returned. I stopped at the services, purchased 10l of fluid and added 4l to the tank, before it overflowed. The error warnings continue, I have 600 miles left before I can’t start the car and I now need to contact the dealer again with this same problem.
I’m worried that perhaps the initial issue never really went away and that my car will be 5 years old this October and outside the period that Citroen may look favourably on a warranty replacement of the tank. I did open a case with Citroen UK 15 months ago and they did appear helpful, but I had to inform them that the local dealer could find nothing wrong. Hopefully, I can take some comfort that this record will be useful in the event of a new tank being needed.
BTW, I've just checked and I don't think that I have a modified AdBlue cap fitted on my car.

[wheeler]

To be fair i have found when you reset the denox system if it hasn't cured the issue it normally re occurs within 500 miles or less.

[GiveMeABreak]

.....I’m worried that perhaps the initial issue never really went away and that my car will be 5 years old this October and outside the period that Citroen may look favourably on a warranty replacement of the tank. I did open a case with Citroen UK 15 months ago and they did appear helpful, but I had to inform them that the local dealer could find nothing wrong. Hopefully, I can take some comfort that this record will be useful in the event of a new tank being needed.

That'll be the big debate, as the 5 years is coming up in a few months, so my advice is get it officially reported now and keep records of emails / conversations, as even if they can't get it booked in for a while that's hardly your fault. It may well cost you the £120 diagnostic charge which you will have to pay, but also take photos of the light and warning messages when safe to do so as additional evidence of the recurring fault happening now.

It may well be a blocked injector (from crystallisation) or the tank failing, but fingers crossed you will get some support - but don't hang about and if your other dealer can't see it, call another dealer.

[citroen since 1973]

Thanks very much, both, for your prompt responses. I'll endevour to get the car seen tomorrow and report back when I have more news, Paul.

[Paul-R]

Funnily enough I've just had to reinitialise the Denox system on my 308 today. And that was about 500 miles after having to do it some three or four weeks ago - the first time since changing the tank.

[wheeler]

PSA will now do partial covering of costs on urea tanks up to 8 years or 131,00 miles.

[citroen since 1973]

I spoke to Budgen Motors this morning, they're the only Citroen dealer in Shropshire and they are fully booked until 30th August!!! However, they can do an AdBlue system reset, for £25 and this should give me an additional 700 - 800 miles. They've advised me to contact them when I get down to 200 miles and pop it in. I also mentioned that it looks like my car should have had a new style tank cap fitted. Having "never heard" of a single AdBlue tank problem 15 months ago, they now admit to having several issues, with new tanks being required, recently! Due to the time scale, it looks like I should also try and find another garage to look at this for me, but I don't know of one local to Telford, where live. If anyone knows of a place they can recommend, please let me know.

Also, I've noticed on the cactusforums.co.uk, where there is an extensive thread on the C4 AdBlue problem, many people now seem to be electing to bypass the system completely, either by remapping the electronics, or physically removing the bits of the system, or a combination of the two. I must say that I do consider this action to be wrong from a health perspective, but so many people now seem to be having to pay large bills to rectify something which is clearly a fault of the manufacturer, that I can sympathise with their plight and understand their decision. I'm pleased to see that PSA have extended the "partial" cost of replacement tanks to 8 years/131,000 miles, but the amount they contribute does seem to vary greatly, from claim to claim and after all, it is a PSA fault, not the car owner!

In addition to the above, I also read a message on cactus from a French contributor, who posted a link to the French consumer defense association - UFC-Que Choisir. They announced on 12.7.23. that they are "going to seize the General Directorate for Consumer Affairs and Fraud Control concerning the numerous failures linked to the AdBlue pollution control system" - https://time.news/ufc-que-choisir-accus ... f-failure/

Watch this space and fingers crossed!

[RichardW]

The cap only applies to early cars - the modified design was fitted as std from about 2016 when the filler was in the car. I suspect yours has a breather elsewhere.

I imagine the first time they read the codes, got the generic 'it's not working' code and then reset it. They need to work through the cycle to check that it is doing what it's supposed to be when it's supposed to be to pin down the issue. Don't let them play parts darts at your cost!!

[citroen since 1973]

Thanks RichardW, the cap info is reassuring. I take your point about the checks that they need to carry out and about me not having to pay for them playing "parts darts" however, I have no idea how to realistically prevent this! No, I don't trust them, or their ability and the many cases of owners being ripped off an mistreated only supports my distrust, but I'm a retired builder, with little knowledge of modern car mechanics. They have me over a barrel and there's little that I can do about it!

[Paul-R]

...they can do an AdBlue system reset, for £25 and this should give me an additional 700 - 800 miles.

See my post here viewtopic.php?p=763808#p763808

[citroen since 1973]

Thanks Paul-R, but do you have to convince your car that you've fitted a new tank every 700 miles? I don't have any equipment to do this or, I guess, the technical nohow, but I do like your work-around. BTW, my wife and I love your footnotes, as we're often going into that room with no idea why!

[Paul-R]

It's really only just started happening so I don't know for sure. But a brief timeline might help. I'm doing a lot less mileage than I used to which complicates thing in my mental map!

Sep 29 2020, 68,966 miles, new tank fitted
about 10,000 miles later
July 2022, 700 mile countdown started. 50 miles to go I reset the engine ECU so about 79,000 miles.
That lasted until mid July this year, about 84,500 miles, so about 5,300 miles later.
That lasted until about 85,400 miles before the countdown started again, so about 900 miles later.

Which brings us up to date at 85,973 miles when I've just done another reset. I've no idea how long that will last (I haven't driven the car yet) but, say, 500 miles before the light comes on again plus 700 mile countdown gives 1200 miles I hope.

[GiveMeABreak]

Also, I've noticed on the cactusforums.co.uk, where there is an extensive thread on the C4 AdBlue problem, many people now seem to be electing to bypass the system completely, either by remapping the electronics, or physically removing the bits of the system, or a combination of the two. I must say that I do consider this action to be wrong from a health perspective,

It's also illegal (as may already know) to bypass or cripple the emissions system for public road vehicles and this Forum doesn't condone any such action. It's a system we are stuck with, but Wheeler indicates in a recent post that PSA are extending / providing some financial contribution towards the replacement of the tanks now for up to 8 years. Obviously the degree of financial contribution will be dependent on age, mileage and service history I expect - if anything like their other warranty conditions.

[citroen since 1973]

A bit of an update. Earlier this week I stumbled across https://chevroncitroenspecialists.com/ at Brewood, nr Wolverhampton and called them for advice. It turns out that James used to be the workshop manager for a company in Telford that serviced my Citroen cars, many years ago. He's fully PSA trained and suggested that I bring my C4 in for him to check. One hour later, he'd done a dyno check of the car, cleared the fault codes and carried out a denox system reset. Thankfully, as in the previous check, at Budgen's, he could find no problem with the AdBlue tank and thinks that I may have an intermittant fault, or possibly an injector issue. As before, I'm now driving with no issues, fingers crossed and hoping that all is well. This experience cost me £25 (although his credit card maching wouldn't work and I only had £20 cash, which was acceptable). All in all, a very pleasing and reassuring find and a good contact for the future.

[GiveMeABreak]

Thanks for the update - if there is an ongoing issue, it will no doubt re-present itself again, especially if it is electrically related - outside of the harness wiring to the adblue tank, plus there are a lot of internal electronics that can rust and cause intermittent issues. So the best thing is to let any fault develop.