Little-known car button can instantly reduce fuel consumption by 12 percent

Drivers should continue to see falling unleaded petrol prices as average costs stand around 168.36p per litre. Diesel motorists face more expensive costs, however, with the RAC predicting that no price changes are forecast.

Prices have lingered at around 183.19p per litre after falling from the all-time record highs seen at the beginning of July.

It is feared by some that fuel prices will begin to creep up again in the near future.

As a result, many have started to adopt fuel-saving techniques to reduce the amount of time and money they spend at petrol stations.

Some have even started giving advice on social media to help their followers save money on motoring costs.

READ MORE: Simple car trick can help drivers slash fuel consumption with 20p coin

When the car is motionless or out of gear, the fuel supply and connection to the engine are halted.

This is done to prevent idling which wastes money on fuel and produces harmful emissions without the vehicle going anywhere.

For drivers using this feature, fuel economy could increase by up to 12 percent.

The Royal College of Physicians estimates that 40,000 deaths a year in the UK are linked to air pollution, with engine idling contributing to this.

Rule 123 of The Highway Code looks at “the driver and the environment”. 

It states that drivers must not leave a parked vehicle unattended with the engine running or leave a vehicle engine running unnecessarily while the vehicle is stationary on a public road.

A study by the US Department of Energy found that heavy-duty and light-duty vehicles combined waste about six billion gallons of fuel annually.

Around half of this is believed to be from personal vehicles which create around 30 million tonnes of CO2 every year just from idling.

A study by Polytechnic University of Madrid compared the engine emissions of two four-wheel drive cars and found that the one fitted with automatic stop-start functionality recorded 20 percent lower emissions than the vehicle without this technology.

The emissions-lowering capability of stop-start systems is particularly important in towns and cities, where traffic is likely to be stationary for longer.