What Is AdBlue and Can You Accidentally Misfuel It?
AdBlue is becoming standard on modern diesel vehicles in New Zealand. Putting diesel in the AdBlue tank — or AdBlue in the fuel tank — is a costly mistake. Here is what drivers need to know.
What Is AdBlue?
AdBlue is a diesel exhaust fluid — a solution of urea and deionised water — used in Selective Catalytic Reduction (SCR) systems to reduce nitrogen oxide emissions from diesel engines. It is now fitted as standard on most Euro 6-compliant diesel vehicles sold in New Zealand since 2017, including popular models from Toyota, Volkswagen, Mercedes-Benz, and Ford.
How AdBlue Misfuelling Happens
There are two common AdBlue misfuel scenarios. The first is filling the AdBlue tank (typically a separate, smaller filler cap near the main fuel filler or in the boot) with diesel or even water. The second — and far more damaging — is pouring AdBlue into the main diesel fuel tank. AdBlue is highly corrosive to fuel system components and will damage injectors, the high-pressure pump, and fuel lines rapidly. Even a small quantity of AdBlue in a diesel tank requires immediate manufacturer-spec fuel system recovery.
What to Do
If you suspect an AdBlue misfuel — in either direction — do not start the engine. An SCR system exposed to diesel will crystallise and block the catalyst; a fuel system exposed to AdBlue will begin corroding within minutes of running. Call EEK Mechanical on 0800 769 000. Our technicians are trained to handle AdBlue contamination scenarios and can advise on whether the SCR system or fuel system is affected.
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