CLEANING UP NEED NOT COST MORE
FUEL supplement Adblue is increasingly appearing in Euro 6 compliant cars and pickups and is proving a less than straightforward, or popular, piece of vehicle technology.
Adblue is a low tech bypass to ever tightening Euro emissions regulations, particularly from diesel engines and involves adding a second tank to the car with an additional filler nozzle normally (but not always) located next to the fuel filler cap.
It’s HGV technology that has made its way to the smaller vehicle market.
A selective catalytic reduction (SCR) system injects a mixture of water and urea into the vehicle exhaust gases to clean up noxious emissions.
BMW, Audi, Volkswagen, Mercedes and Citroen commonly use Adblue, (often identified by Blue badging). It can equate to five per cent of diesel use and add significantly to vehicle running costs, particularly as — like diesel — Adblue consumption increases as speed rises.
When an Adblue tank runs dry, the engine goes into “limp” mode and will refuse to restart until replenished.
Adblue containers must not be kept inside vehicles — it is unpleasant stuff. An eye and lung irritant and corrosive — any spills will damage paint- work and the vehicle interior (some makes place the reservoir inside the car requiring a spanner to open it). Adblue should be handled as you would battery acid, or paint stripper.
A less obvious irritant and hidden expense is that once opened Adblue containers cannot be stored — it absorbs contaminants from the air and unused fuel additive should be disposed of immediately.
Price varies dramatically so shop around to minimise additional expense. Never dilute Adblue or put water in the reservoir, the SCR system will fail completely and a substantial repair bill will not be covered under warranty.
The good news is that not all vehicle manufacturers have opted to go down the Adblue route. Subaru and Isuzu have both invested heavily in advanced engine technology that minimises harmful N02 emissions and avoid the use of Adblue or other fuel additives through their complete vehicle ranges. This approach results in no additional complexity for the vehicle driver when refuelling, no additive costs and no infuriating engine “limp” modes or refusal to restart.
Isuzu’s D-max employs an innovative self-cleansing chamber within the pick-up’s exhaust system. As the vehicle is being driven it constantly monitors its own emissions and self-cleanses when required through an additional burn process — no Adblue or other expensive additives are required. The D-max continues to drive normally through the regeneration process and the driver will be unaware it’s even happening.
For the Subaru or Isuzu driver significant manufacturer investment means life remains pleasantly free of new complexities or specialist knowledge, yet their vehicles still deliver enviably miserly levels of fuel consumption in real world driving conditions.
Long may that approach continue and hopefully other manufacturers will mimic them.
It’s worth noting that in the most heavily regulated emissions market — the USA — Subaru outsell all the German brands combined.
Keeping technology simple, and user friendly may be just what customers really want?
The Isuzu Centurion and Subaru Boxer (above) engines both benefit from built-in self-cleansing technology