What is misfuelling?

Causes, risks and consequences of choosing the wrong fuel at the petrol station.

At a glance

The word misfuelling means refuelling a vehicle with the wrong fuel, e.g. petrol instead of diesel, E10 petrol instead of regular unleaded, diesel instead of petrol, Ad Blue in the regular tank. This happens more often than you think (see below) and is always associated with hassle, costs and loss of mobility.

In the majority of cases, it is a question of falsely refuelling diesel cars with petrol, as this is easiest purely from technical point of view. The 21mm diameter of the petrol nozzle is smaller than that of the 25mm diesel nozzle and therefore fits well into the tank opening of a diesel car. According to the ADAC, however, it is also possible, with many current models from well-known manufacturers, to refuel a petrol car with diesel despite the larger diameter of the nozzle.


The most common reasons for misfuelling are:

- Distraction and lack of focus
- Stress, deadline pressure or tiredness when driving at night
- Several types of fuel available on one multi-dispenser pump
- Confusing labels on the pump nozzles
- Foreign designations such as Nafta, Gazole
- Stress from traffic jams or heat in summer
- Habit becomes a problem with changing vehicles, e.g. company car, second car, rented car, etc.

How often and where do drivers misfuel?

Germany: 200,000 times a year

Great Britain:
 133,000 times a year

Netherlands: 25,000 times a year

Belgium: 18,000 times a year

Norway: 15,000 times a year

Austria: 14,000 times a year

Switzerland: 10,000 times a year

Since misfueling is not classified as a breakdown, does not necessarily require the intervention of the automobile clubs and is usually not considered an a covered event by insurance, there are no accurate national statistics on this.

The real number of misfuelling cases is estimated to be many times higher than what is known, since, if noticed on time, petrol stations, car repair shops or companies specializing in misfuelling can also be called for help.

Avoidable damage for the driver, the car and the environment

Diesel lubricates, petrol blocks. Misfuelling causes about 1 in 10 engine failures.

Misfuelling causes problems with the manufacturer's warranty and liability, as it is often classified as incorrect use of the vehicle and not as a breakdown.

Millions of liters of fuel have to be disposed of as hazardous waste, which is expensive and harmful to the environment.

Each incidence of misfuelling can cost drivers and companies between £300 and £10,000.

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