Audi A4 Avant - Adblue Range

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Mon 30 Jan 2023 16:58
Audi A4 Avant - Adblue Range - paul45

Hi All, long time since I posted on the tech matters forum - hope all is well with everyone !

Here's the fault - Emissions warning light illuminated and at the same time the DIS states "Adblue fault - 700 miles until car will not re-start". So, I had to drive to Glasgow from home today for work (210 miles), so car now states "450 miles until car will not re-start". So it seems to be counting down OK. I will need to drive 210 miles back home, and then I have managed to book the car into a dealer 120 miles away (local Audi dealer saying - no appointments until the end of April......). In theory I should be OK then - i.e. I will have around 130 miles to spare.

So my question is, if I set off with less miles than I know I need to get to this dealer, will the car keep driving, even if it runs out of adblue range, or will it literally stop once it counts down to zero, I assume this won't happen, although it could go into limp home mode, and reduce the power / speed, which will be a bit of a pain if I'm on the M6.

I realise that if I stop and re-start and I'm out of range then of course the engine will not re-start, but will it stop if I'm travelling? Goes without saying I'll turn the stop/start off....

Wonder if anyone has had this problem before?

Thanks in advance

Paul

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Mon 30 Jan 2023 17:09
Audi A4 Avant - Adblue Range - Andrew-T

When it says 'Adblue fault' does it mean there is an actual fault, or just that you should top up the Adblue reservoir ? Surely you can do that - my daughter does it on her Jag, and she knows SFA about cars ....

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Mon 30 Jan 2023 17:15
Audi A4 Avant - Adblue Range - paul45

Under normal conditions the adblue level emits a warning at 1000 miles before, and then I top up with 10 litres.

So I topped up with 10 litres once I got the 700 miles warning, but it's made no difference. usually 10 litres is good for about 10k miles, so it can't be that. I suspect a sensor on the adblue tank is not working so it's telling the ECU that it's on the reserve tank only with a limited range.

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Mon 30 Jan 2023 17:17
Audi A4 Avant - Adblue Range - paul45

Under normal conditions the adblue level emits a warning at 1000 miles before, and then I top up with 10 litres.

So I topped up with 10 litres once I got the 700 miles warning, but it's made no difference. usually 10 litres is good for about 10k miles, so it can't be that. I suspect a sensor on the adblue tank is not working so it's telling the ECU that it's on the reserve tank only with a limited range.

Should have said DIS states "adblue fault" rather then adblue warning

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Mon 30 Jan 2023 18:46
Audi A4 Avant - Adblue Range - elekie&a/c doctor
If the range is not being calculated correctly, then it’s possibly a faulty adblue level sensor system . It’s part of the adblue tank and not available as a separate part . Not a cheap fix. I think the part alone is over £600 .
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Mon 30 Jan 2023 19:32
Audi A4 Avant - Adblue Range - paul 1963
If the range is not being calculated correctly, then it’s possibly a faulty adblue level sensor system . It’s part of the adblue tank and not available as a separate part . Not a cheap fix. I think the part alone is over £600 .

Wonder if it could be a fault with the 5th injector? Any way you could find someone with a code reader?

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Mon 30 Jan 2023 21:50
Audi A4 Avant - Adblue Range - elekie&a/c doctor
That’s another possibility. Adblue crystallises at low temperatures and can block up the system . That’s why a heater is installed in the adblue tank . Adblue is around 60% water .
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Tue 31 Jan 2023 10:41
Audi A4 Avant - Adblue Range - paul45

Thanks All - could be either - fortunately it's still under Audi warranty, just making sure I have enough range to get to the dealers !!

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