# 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.

- Canonical URL: https://www.eek.nz/news/adblue-misfuel-what-is-adblue
- Published: 2024-06-03
- Author: EEK Mechanical
- Publisher: EEK Mechanical, a trade name of Forman Pacific, LLC

## 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](tel:0800769000). 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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Source: https://www.eek.nz/news/adblue-misfuel-what-is-adblue