Ad Blue usage

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Nov 11, 2009
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Where have I been?. Had to look up what Adblue is. Have had diesel engines since about 1980, done many thousands of miles. Do remember when abroad at garages motorist were topping up their fuel with an additive but did not do I myself. Up till today my Skoda has done 115k without problem, but it is serviced each year without comment at these times
Does your Skoda require adblue ? It’s there for a purpose not like the old shots of Redex of yesteryear. If it did require adblue you certainly would not have done 115 k miles without putting any in. It does nothing for the car’s performance or longevity it’s there to reduce diesel NOX emission.
 
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Jun 16, 2010
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How do you get your hands dirty adding AdBlue? Our Passat has a filler point at the side of the fuel filler. I think some cars had the access through the middle of the spare wheel (or at least where the spare wheel used to be!)
Per Skoda, AdBlue has only become a requirement on Euro6 engines - or since about 2015.

The filler point is screwed to the bulkhead under the bonnet. That, and you can cause issues by overfilling it as the filler tube runs from the bonnet right under the length of the car.

Unlike my Santa Fe, which is next to the filler like your Passat.
 
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On my previous V90 (D4), the ad-blue was also next to the fuel filler but it must have been a convoluted/restricted route as it took ages to fill….. at least I don’t have that on the current petrol model.
 

Mel

Mar 17, 2007
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On our Discovery Sport the Ad Blue filler was under the bonnet and at an awkward angle if you were pouring from a large container. Danger of it going everywhere and then decorating the engine with urea crystals ( yes ad blue is essentially pee). We also got Halfords to do it. Our current tow car doesn’t use it.
Mel
 
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Does your Skoda require adblue ? It’s there for a purpose not like the old shots of Redex of yesteryear. If it did require adblue you certainly would not have done 115 k miles without putting any in. It does nothing for the car’s performance or longevity it’s there to reduce diesel NOX emission.
Correct, when MOT have been done no mention has ever said anything about it. When motor homing in the nineties there were many people saying about Millers oil being the best for performance etc which like most things they are soon forgotten, so does this additive really work?.
 
Nov 11, 2009
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Correct, when MOT have been done no mention has ever said anything about it. When motor homing in the nineties there were many people saying about Millers oil being the best for performance etc which like most things they are soon forgotten, so does this additive really work?.
What it does is reduce NOX levels in the exhaust. So yes it does work but cit doesn’t do anything for engine performance. The use of Urea (adblue) is a well established process of Selective Catalytic Reduction which ships introduced at least 20 years ago. It will not be forgotten as long as there are diesel vehicles/engines. If your car requires it then it will not go very far without it being replenished.
 
Mar 14, 2005
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Correct, when MOT have been done no mention has ever said anything about it. When motor homing in the nineties there were many people saying about Millers oil being the best for performance etc which like most things they are soon forgotten, so does this additive really work?.
I am led to believe it does work, but whether it's true or not is overshadowed by legal requirement, where if a EU6 rated vehicle is built with a urea (Adblue) additive system, if the reservoir empties whilst the vehicle is in motion, the engine management warning will be produced, and after a short while, the performance of the engine will be limited to "limp home" mode. Once the engine stops the engine management system will prevent the engine from restarting until the reservoir is replenished. Thats why its not a good idea to run out.

Running without the additive is unlikely to damage the engine, as its added after the exhaust manifold, but whether it might compromise the catalytic converter I don't know.
 
Nov 6, 2005
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I am led to believe it does work, but whether it's true or not is overshadowed by legal requirement, where if a EU6 rated vehicle is built with a urea (Adblue) additive system, if the reservoir empties whilst the vehicle is in motion, the engine management warning will be produced, and after a short while, the performance of the engine will be limited to "limp home" mode. Once the engine stops the engine management system will prevent the engine from restarting until the reservoir is replenished. Thats why its not a good idea to run out.

Running without the additive is unlikely to damage the engine, as its added after the exhaust manifold, but whether it might compromise the catalytic converter I don't know.
At least as far as my Euro-6 VW Touareg goes - running out of Adblue won't put the engine into "limp mode" - it'll continue running normally until it's switched off, then it won't restart - the electronics monitor the Adblue level and give a warning at 1500 miles from empty, which is repeated every 100 miles - NOTE when towing, the 100 mile countdown occurs every 40 miles due to the engine working harder and using more diesel.
 
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Jul 18, 2017
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Running without the additive is unlikely to damage the engine, as its added after the exhaust manifold, but whether it might compromise the catalytic converter I don't know.

Do you know how it actually works as I have zero idea and would be interested. Thanks.
 
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Nov 6, 2005
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Much better and now have an understanding. Is there really a need for the DPF to be fitted or does that trap other nasty stuff that the Adblue cannot eliminate?
The DPF deals with soot particles which are quite different to the NOx gases although both are very harmful to people.

It may be worth noting that NOx, which is harmful, will naturally break down over time into Nitrogen (N) and Oxygen (O) which are both vital for life but the high levels of CO2 in the atmosphere prevent that natural breakdown in urban areas which is why Low Emission Zones (LEZ) are being introduced to impose fines on the use of older vehicles with high NOx outputs.
 
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The DPF deals with soot particles which are quite different to the NOx gases although both are very harmful to people.

It may be worth noting that NOx, which is harmful, will naturally break down over time into Nitrogen (N) and Oxygen (O) which are both vital for life but the high levels of CO2 in the atmosphere prevent that natural breakdown in urban areas which is why Low Emission Zones (LEZ) are being introduced to impose fines on the use of older vehicles with high NOx outputs.
The levels of carbon dioxide in the atmosphere don’t affect the decision to introduce ULEZ which are targeted at reducing ground level pollutants namely particles PM2.5 and less, and NOX. Both of which are deemed harmful to health. A by product of DPF and SCR is increased carbon dioxide levels from exhausts. But the balance of advantage still lies with reducing exhaust emissions at street level.
 
Nov 6, 2005
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The levels of carbon dioxide in the atmosphere don’t affect the decision to introduce ULEZ which are targeted at reducing ground level pollutants namely particles PM2.5 and less, and NOX. Both of which are deemed harmful to health. A by product of DPF and SCR is increased carbon dioxide levels from exhausts. But the balance of advantage still lies with reducing exhaust emissions at street level.
CO2 levels are related to LEZ introductions as well as London's ULEZ - it's the higher levels of CO2 that cause temperature inversion over urban areas which prevents the NOx breaking down naturally and so causes high levels of NOx in urban areas - which is why some motorways in urban areas are having reduced speed limits imposed to try to improve air quality.
 
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CO2 levels are related to LEZ introductions as well as London's ULEZ - it's the higher levels of CO2 that cause temperature inversion over urban areas which prevents the NOx breaking down naturally and so causes high levels of NOx in urban areas - which is why some motorways in urban areas are having reduced speed limits imposed to try to improve air quality.
Came back from a weekend in Chester via M6 and M5 and the elevated M5 in Birmingham has 60 mph fixed limit with signs informing it is for air quality improvements. Chance to do 60 mph would have been welcomed. 😂
 
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Mar 14, 2005
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There may be a difference in the detail behind decisions to introduce ULEZ etc one of the and the use of Urea exhaust treatments and particulate filters etc, the root cause is high pollution levels. There is a broad spectrum of pollutants, and different processes produce each bring varying mixes of pollutants, but on of the common constituents seems to be CO2, and thats why its often used as a simple indicator for the public to understand to compare levels of pollution.
 
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There may be a difference in the detail behind decisions to introduce ULEZ etc one of the and the use of Urea exhaust treatments and particulate filters etc, the root cause is high pollution levels. There is a broad spectrum of pollutants, and different processes produce each bring varying mixes of pollutants, but on of the common constituents seems to be CO2, and thats why its often used as a simple indicator for the public to understand to compare levels of pollution.
Few mention carbon dioxide levels in cities as they are well below the levels that HSE use for industrial exposure. I’ve been in environments where exposure to 1% for long continuous periods brought no increase in morbidity. In London carbon dioxide emissions have reduced 45% since peak emissions in 2000, despite in increase in population. The emissions deemed harmful to health are fine particulates and NOX and it’s these that LEZ/ULEZ are aimed at reducing.

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