Selective catalytic reduction and AdBlue®
Some of our latest Volkswagen diesel cars have a Selective Catalytic Reduction system (SCR) installed. The system, which helps the vehicle meet Euro 6 emission standards, has a separate tank which contains a liquid known as AdBlue. Some vehicles have a filler next to the regular diesel cap while others may be located in the boot by the spare wheel well.
The AdBlue is injected into a specially modified part of the exhaust system in small amounts. This helps to reduce oxides of nitrogen emissions (NOx).
AdBlue is now common across the motor industry and is not exclusive to Volkswagen.
Why is it necessary?
All cars type approved from 1 September 2014 and all new cars registered from 1 September 2015 must meet the new EU6 emission standards. SCR systems help the latest generation of diesel engines to meet the new requirements. Volkswagen petrol engines do not require AdBlue.
Important things to remember about AdBlue
AdBlue is a consumable and will require topping up.
Its usage is linked to fuel consumption, so driving style, vehicle size, load, outside temperature, AdBlue tank capacity and a number of other factors will determine top-up frequency.
AdBlue usage is between 0.5 and 2.5 per cent of diesel consumption. It is not possible on all models to check the level but our cars do give a warning from when the range is down to 1,500 miles until it reaches zero.
When AdBlue runs out and the engine is turned off. The engine cannot be restarted until at least 5.7 litres of AdBlue fluid has been added.
AdBlue is not added to the diesel fuel tank or vice versa.
It is not recommended that spare containers of AdBlue are kept in your vehicle. The dash display will provide plenty of warning should you require a top-up. It is available from a number of outlets, not just Volkswagen retailers.
Adblue costs around £1.50 per litre and can be purchased from our Parts Department in easy fill containers or we can apply larger amounts for you with our specialist equipment.