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Reduce the car’s fuel consumption by simple means

Catalytic converter

  • The catalytic converter transforms the harmful substances in petrol/diesel into carbon dioxide and water with the help of chemical reactions.
  • 80–95% of the harmful substances are eliminated.
  • The catalytic converter has an operating temperature of 400–600°C, which means that it takes a while for it to function optimally.
  • In Sweden, all cars manufactured after 1989 must have a catalytic converter.

Engine heater

The engine heater is located underneath the bonnet and is used to warm up the engine. There are many benefits to an engine heater:

  • The catalytic converter starts working sooner.
  • Lower fuel consumption.
  • Less wear on the engine.

How long the engine heater should be turned on

  • +10 °C = 20 minutes before leaving.
  • 0 °C = 60 minutes (1 hour) before leaving.
  • -20 °C = 90 minutes (1.5 hours) before leaving.
Car with caravan.

It is not only the weight of the caravan that increases the fuel consumption. The additional air resistance also plays a part.

Keeping the engine heater on for too long is unnecessary and bad (as it uses up electricity without any benefit).

Reduce air resistance

Walking around in a storm with a large open parasol in front of you is hard. The same is true for the car. The fewer wind-catching areas there are, the less fuel is needed to propel the car. Things to consider when it comes to air resistance:

  • Take off rails and roof boxes when not in use.
  • Avoid large spoilers etc. (The aerodynamic benefits are often negligible on regular cars).
  • Drive with the windows shut. An open side window or sunroof disrupts the airflow around the car, which leads to greater air resistance.
  • Avoid tyres that are too wide.

Correct tyre pressure

A steel marble will roll better than a deflated football. The same is true when it comes to the tyres of the car. Tyres with high air pressure will roll more easily than tyres with less air in them. The more easily the car rolls, the less fuel it takes to propel it. It also reduces the wear on the tyres.

10–15% over the tyre pressure indicated in the manual is usually best. Read more about tyre pressure in the section on tyres.

Green tyres

These days, toxic HA oils are prohibited within the EU. But there are other aspects that make your tyres more or less environmentally friendly. Tyres with low rolling resistance and recycled rubber are good for the environment. If you want to be even more green, you can buy ecolabelled tyres.

Use the air conditioning sparingly

The air conditioning (AC) uses a lot of energy. If you turn off the AC, you can save 5–10% in fuel consumption.

Wash the car correctly

You should wash your car in a location intended for that purpose, such as a petrol station. These places have special floor drains that collect any harmful residues from the wash.

Waxing your car not only makes it look good – the wax also forms a protective film which means that less dirt sticks to the car. This in turn means fewer washes are necessary, which is good for the environment.

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Last updated 2021-01-22.