• Air conditioning increases fuel consumption. Conversely, the radiator on in the winter does not "burn" more as it uses the already warm engine air.
• Check tire pressure often. Deflated tires create further drag and therefore increase fuel consumption. They may charge up to 7% of consumption.
• Sharp driving and changes in speed and revs also greatly increase petrol burn. Smooth driving with the least possible turns and the fewest speed fluctuations is certainly the most economical.