Ad Blue - final help please

[rellis74]

Please can anyone offer some final advice for me on the usual ad-blue issue.

I had my 2018 T6 (70,000 miles) parked up for 6 months and during that time the battery went flat. I've been driving it again for about 3 weeks and suddenly got the dreaded 650mile no engine re-start message. I hurriedly put 5l of adblue in whilst I was out and it made no difference. I then tried to top up again the next day but after about 2l the adblue was pouring out of the nozzle - so clearly too full.

I read through the threads here and followed the advice to drain the tank - managed to siphon about 11l out of the tank adn then added a bottle of the decrystaling fluid to see if that woudl get any crystallisation off the senor. following this I did the 30 sec ignition re-set thing and nothing changed - now down to 550 miles. I then drove round for a day and the MFD suddenly changed to say I needed to add min 0.75g to max 0.75g of ad-blue - however the yellow warning and 500mile no re-start was still showing. I added 0.75g of adblue and also tried the 30sec reset thing again. following this is is now down to 500m warning and the ad-blue level thing has disappeared again.

I've now booked it into the Manchester VW sensor hoping they will just need to do a reset for me. Does anyone have any other advice, I really don't want it to go in and be told I need to spend £1600 on a new tank sensor. I think id rather just get the adblue mapped out of the system if that is their solution (I do such low mileage and plan on keeping the van for a long time). If mapping is the solution, does anyone recommend someone near Stockport that can do this for me, or should I just take the plunge and head up to Pendle and get the engine remapped (if they do both?) and have ad-blue taken out at the same time?

 

[manfrotto]

It could be that it needs the software update for a known issue....

Post in thread 'Software up to date?'

23 Sep 2022

The engine software version is 4047. (2017 102ps 5 speed manual Highline converted panel van). Does this need to be updated? Can this only be done by a main dealer?

There is an update available - version 6163.

The update should cure a few niggles - mainly fault P20EE and sudden AdBlue range drop (to 1000 km/650 miles).

A before/after comparison here:

[T6_measured] NOx emissions, AdBlue consumption, DPF regeneration - Before and after ECU update

Introduction An update campaign for T6 EU6 diesel engines took place in 2019-20. Affected engines were on van of model years MY16-MY18, including some of MY19. For M1 class (passenger carriers, VIN WV2...) the update was an official recall. For N1 class (VIN WV1....) the update was not...

www.t6forum.com

Carista (today it won’t let me, or give any fault code details, unless I sign up...

• mmi

• 

 

[Ayjay]

I know bogger all about the technical aspects of all this adblue stuff but I do know that mine went into VW Swindon with what seems to be all the usual / common adblue issues (ie. as above and as reported by quite a few on here including me). They assured me that a software update would sort it all out and it did but only temporarily. The problems all came back again, disappeared, came back etc. VW were talking progressively longer telephone numbers to fix it by changing the various components involved without any guarantees of success but I wouldn’t play their game and I’m currently in remission. We’re doing a 190 odd mile drive to Cornwall next week and will see what occurs.

 

[ben5560]

I had Adblue issues like this on my Q5 2018, and Audi could not tell me what was wrong other than to 'change the entire tank' at a cost of 2k, and the tank was not in stock anywhere anyway!

I don't know how the T6 differs to the Q5, but on the Q5 system at least you have:

• Line Heaters (to stop the Adblue crystalising
• Level Sensor (ultrasonic)
• Pressure Sensor next to the pump
• Pump
• Injectors

On mine i had a Pump range performance error code, I could get the motor to spin using VCDS but it would never actually draw fluid. The pressure sensor originally was reading -170hpa and so it was either in a vacuum or faulty. Changed that for a new one, no joy. Changed the pump, no joy. Changed the battery(!), no joy.

This is perhaps why VW/Audi just say new tank, instead of spending money chasing faults.

But when that countdown comes up, there is a ODIS/VCDS basic setting that takes about 45 minutes. It will get the engine/cat up to temp quickly to be able to test the system. Alternatively it needs to go on a test drive, and when the car sees that its working it will turn off the countdown.

Ultimately you need to scan it with VCDS/OBD11 and find the fault codes first.

P.S. Annoyingly, all i did was top up the system with adblue! I think the guidance on the T6 is to wait 30 seconds before turning on the engine, i wonder if i had the same issue on my Q5

 

[monkeybusiness]

I think the guidance on the T6 is to wait 30 seconds before turning on the engine, i wonder if i had the same issue on my Q5

Thats interesting. Anyone else heard this?

 

[Ayjay]

This is perhaps why VW/Audi just say new tank, instead of spending money chasing faults.

This was almost my experience with my 2014 reg ex-demo Q5. Even reading the fault codes with their 'sophisticated' kit, Audi Tetbury couldn't say what the exact issue was and could only offer progressively changing stuff until /when / if the problems went away. Not sure whether that was due to technical incompetence or just chasing pound notes but I wasn't willing to sign up for what looked like a potential blank cheque so I went down the illegal 'mapping out' route. 3 years later, the now aging Q5 is otherwise as good as new apart from a couple of minor scrapes (but TBH, I'm just waiting for something big to break when I'll probably change it without a lot of complaint).
I'm still having the mental debate with myself about whether I go down that path with my T6 at some point.

 

[ben5560]

Its because their software with what they 'Guided Fault Finding' just says do this, try this and then spits out 'new tank' instead of actually spending time to read the data. I got down to learning about the motor pump, what data is read by the Adblue module...etc but in the end it didnt help me. Hard to know whether its the Software locking it out or Hardware.....

At least on the earlier Q5 like yours, the pump module comes out of the tank like this:



This is not the case on the later one, where that module is literally part of the tank and can not be changed so the whole tank needs changing in one go...great idea Audi.

 

[manfrotto]

This is a service schedule for an Audi Q3, which states renewing ADblue fluid every 2 years and recalibrating the system!


No such thing mentioned for VWs though that I have seen. - Food for thought though.

 

[ben5560]

This is a service schedule for an Audi Q3, which states renewing ADblue fluid every 2 years and recalibrating the system!

View attachment 324051
No such thing mentioned for VWs though that I have seen. - Food for thought though.

Probably a good idea, I think it has a shelf life

 

[Bigsidavies]

Thats interesting. Anyone else heard this?

Yeah, it's the procedure to get the sensor to detect the new level after a refill. Ign on, wait 30 seconds, new range will be displayed, start van.

 

[Bigsidavies]

Please can anyone offer some final advice for me on the usual ad-blue issue.

I had my 2018 T6 (70,000 miles) parked up for 6 months and during that time the battery went flat. I've been driving it again for about 3 weeks and suddenly got the dreaded 650mile no engine re-start message. I hurriedly put 5l of adblue in whilst I was out and it made no difference. I then tried to top up again the next day but after about 2l the adblue was pouring out of the nozzle - so clearly too full.

I read through the threads here and followed the advice to drain the tank - managed to siphon about 11l out of the tank adn then added a bottle of the decrystaling fluid to see if that woudl get any crystallisation off the senor. following this I did the 30 sec ignition re-set thing and nothing changed - now down to 550 miles. I then drove round for a day and the MFD suddenly changed to say I needed to add min 0.75g to max 0.75g of ad-blue - however the yellow warning and 500mile no re-start was still showing. I added 0.75g of adblue and also tried the 30sec reset thing again. following this is is now down to 500m warning and the ad-blue level thing has disappeared again.

I've now booked it into the Manchester VW sensor hoping they will just need to do a reset for me. Does anyone have any other advice, I really don't want it to go in and be told I need to spend £1600 on a new tank sensor. I think id rather just get the adblue mapped out of the system if that is their solution (I do such low mileage and plan on keeping the van for a long time). If mapping is the solution, does anyone recommend someone near Stockport that can do this for me, or should I just take the plunge and head up to Pendle and get the engine remapped (if they do both?) and have ad-blue taken out at the same time?

You say you syphoned 11l out and then did the 30 sec ign cycle, after which you added the requested 0.75g (3 litres ish). Did you try putting another 7l in of fresh stuff to try to fill the tank? Just wonder if it nbeeds some sort of recalibration after you've emptied the tank.

 

[ben5560]

Thats interesting. Anyone else heard this?

I think it's in the manual?

 

[Ayjay]

This is a service schedule for an Audi Q3, which states renewing ADblue fluid every 2 years and recalibrating the system!

View attachment 324051
No such thing mentioned for VWs though that I have seen. - Food for thought though.

That's interesting but it was never mentioned to me in relation to the Q5! That said, I'm not really surprised and I've often thought to pump the ablue out of the van tank to throw in 'de-crystalisation stuff' and then refill with fresh but I've bottled it every time (no pun intended intended). That said, the last time that I topped adblue up, I did add a bottle of Wynns before a drive up to drive up to Birmingham - the 650 mile warning popped up but disappeared a few miles later (with a personal best) so maybe there's something in snake oil after all.

 

[ben5560]

You say you syphoned 11l out and then did the 30 sec ign cycle, after which you added the requested 0.75g (3 litres ish). Did you try putting another 7l in of fresh stuff to try to fill the tank? Just wonder if it nbeeds some sort of recalibration after you've emptied the tank.

There's a basic setting for that as well in the Engine module 'resetting

That's interesting but it was never mentioned to me in relation to the Q5! That said, I'm not really surprised and I've often thought to pump the ablue out of the van tank to throw in 'de-crystalisation stuff' and then refill with fresh but I've bottled it every time (no pun intended intended). That said, the last time that I topped adblue up, I did add a bottle of Wynns before a drive up to drive up to Birmingham - the 650 mile warning popped up but disappeared a few miles later (with a personal best) so maybe there's something in snake oil after all.

Oh one thing I learnt was to use the adblue pumps, not bottles... Too late now though for the Q5

 

[Ayjay]

@ben5560 - I actually used a 10L adblue bottle the first time a top up was needed after I got the car but every other time it was done by Audi Tetbury at a service.

 

[ben5560]

Thats my plan from now on, VW or Audi can do it - so then its their fault and problem

 

[rellis74]

Thank you - I'm sure mine would eb the VIN VW1 so will need the EMS update. Fingers crossed they don't charge me the earth for this and that if fixes the problem.

 

[rellis74]

You say you syphoned 11l out and then did the 30 sec ign cycle, after which you added the requested 0.75g (3 litres ish). Did you try putting another 7l in of fresh stuff to try to fill the tank? Just wonder if it nbeeds some sort of recalibration after you've emptied the tank.

Yes - I used brand new adblue, I scrapped the 11l that I took out - thought it was a minor sacrifice for the risk of a £1600 new tank.

 

[Howzat]

Here's my advice.
Suck it all out.
Add back 7 litres.
Pray to a god while you wait for the van to do a regen.
Come back and praise me when it resets.

 

[rellis74]

I've basically done that, drained the tank, added Wynn's fluid and 3 to 4l and then driven it around enough for a regen... still no joy so have booked into VW centre. Very frustrating, a good old diesel engine would go for years with nothing much more than an annual oil change, have now had both DPF and Ad Blue issues and I've only done just over 10k miles in the thing since I bought it.