Adblue... going, going, suddenly gone

[scimmiamagia!]

Van say 4500 miles. 100 miles later 3500 miles.

Just driven 30 miles, and it's down to 650 miles left!

What is likely to cause this?

 

[dspuk]

Whatever it is, and likely to be based on van predictions of amount and driving style, needs topping up.

 

[Keith Smith]

Have you checked if it’s leaking out? You may have rodent damage.

 

[Corradobrit]

As dspuk says it's likely the ECU responding to driving status. I've noticed big fluctuations in the range but once everything is warmed up and I've driven for a while the range increases back to where it should be.

 

[B J G]

There have been incidents of Adblue crystalising causing problems.
various suppliers of an anti crystalising agent, eg Wynns

Never used it personally but ----

 

[scimmiamagia!]

Thanks. It’s due a service soon but I have filled it up (ie from 650 miles left) 4 times in 2500 miles. It must be leaking. The fan goes crazy when I finish a journey irrespective of whether I have driven 5 miles or 100 miles on motorway.

 

[scimmiamagia!]

The other thing that we’ve noticed is that it no longer tells us how much adblue to put in. It was saying 4500 thousand miles and then dropped suddenly to 650 miles on a 40 mile journey this morning.

If the sensor is faulty again (I am getting an error code occasionally saying the connection to the sensor is lost) how do you find out how much adblue is in the tank?

 

[Wish]

There have been incidents of Adblue crystalising causing problems.
various suppliers of an anti crystalising agent, eg Wynns

Never used it personally but ----

Hi, BJG… is there a recommended supplier of Adblue, and if so are all other Adblue products “of a lesser degree of quality” for example I’d only use Tesco’s Momentum for a previous car I had. I’ve not had to purchase Adblue yet and just about to watch “California Chris” re. (I presume) when to add “Adblue” [as you might have guessed… we’re at the start of the Campervan journey]

 

[Johnny Rocket]

Hi, BJG… is there a recommended supplier of Adblue, and if so are all other Adblue products “of a lesser degree of quality” for example I’d only use Tesco’s Momentum for a previous car I had. I’ve not had to purchase Adblue yet and just about to watch “California Chris” re. (I presume) when to add “Adblue” [as you might have guessed… we’re at the start of the Campervan journey]

There’s a standard spec. which you can look up, and anything you get from a reputable supplier will adhere to that standard.

Whilst there must be a level sensor in the tank, the display on the dash is actually just a calculated range meter, and not a remaining quantity meter - think of having a driving range-only gauge, and no fuel gauge - yes, it’s rubbish, and another case of the vehicle deciding it knows better than you ;-)

So, if you have a decent indicated range, but then do lots of short or not fully-warmed-up journeys , then the AdBlue dosing used by the engine to effect the desired exhaust after-treatment could, transiently, increase massively - again, imagine a long slow economical journey home which has your fuel range meter showing 50 miles, but you then gun it for 5 miles or so, and the predicted range plummets to zero. It’s exactly the same.

I filled mine the other day when showing a 1000 mile remaining range: after the first 10 litres it said 10,000 miles, and then the same after the next 10 litres . . . only after a short run of ‘normal’ driving did it do a proper recalculation to give ca. 19,000 miles’ range, exactly the interval I have got out of my original and 2nd tankful.

This, at £17:22 for 20 litres delivered, seemed pretty good value:

GreenChem AdBlue 20 Litre Free Pouring Spout

GreenChem offers special AdBlue® canisters with an integrated spout with a capacity of 20 litres. This innovative spout will save you time and effort, thanks to its breathing pipe that help the product to flow out of the can easily. Also, you do not need to look for the spout as it is always...

buygreenchem.co.uk

 

[Wish]

There’s a standard spec. which you can look up, and anything you get from a reputable supplier will adhere to that standard.

Whilst there must be a level sensor in the tank, the display on the dash is actually just a calculated range meter, and not a remaining quantity meter - think of having a driving range-only gauge, and no fuel gauge - yes, it’s rubbish, and another case of the vehicle deciding it knows better than you ;-)

So, if you have a decent indicated range, but then do lots of short or not fully-warmed-up journeys , then the AdBlue dosing used by the engine to effect the desired exhaust after-treatment could, transiently, increase massively - again, imagine a long slow economical journey home which has your fuel range meter showing 50 miles, but you then gun it for 5 miles or so, and the predicted range plummets to zero. It’s exactly the same.

I filled mine the other day when showing a 1000 mile remaining range: after the first 10 litres it said 10,000 miles, and then the same after the next 10 litres . . . only after a short run of ‘normal’ driving did it do a proper recalculation to give ca. 19,000 miles’ range, exactly the interval I have got out of my original and 2nd tankful.

This, at £17:22 for 20 litres delivered, seemed pretty good value:

GreenChem AdBlue 20 Litre Free Pouring Spout

GreenChem offers special AdBlue® canisters with an integrated spout with a capacity of 20 litres. This innovative spout will save you time and effort, thanks to its breathing pipe that help the product to flow out of the can easily. Also, you do not need to look for the spout as it is always...

buygreenchem.co.uk

Your reply is very much appreciated thank you

 

[Johnny Rocket]

Your reply is very much appreciated thank you

My pleasure - I figured the above out only from circumstantial evidence and a knowledge of the processes involved - if I’m wrong I’ll eat my empty AdBlue cans . . . which after 10 swill-outs each are now re-used as handy stackable spare fresh water bowsers, with flexy pouring spouts stored flush in recesses in the can side face !