![](\"https:\/\/cdn.images.express.co.uk\/img\/dynamic\/24\/590x\/fuel-saving-tips-petrol-diesel-prices-little-known-button-stop-start-engine-idling-1667968.jpg?r=1695567137822\")
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“It’s going to automatically shut down your vehicle when it is stationary for a long time, like when you’re sitting at a stop light or maybe through the Starbucks drive-thru.<\/p>\n
“It’s supposed to increase fuel economy and reduce emissions.\u201d<\/p>\n
Stop-start engines are slowly becoming more common with newer, more modern cars having the system.<\/p>\n
Don’t miss… <\/strong> We use your sign-up to provide content in ways you’ve consented to and to improve our understanding of you. This may include adverts from us and 3rd parties based on our understanding. You can unsubscribe at any time. More info<\/p>\n It is designed to cut the engine when the vehicle is stationary, which is then restarted when the brake is released the clutch is engaged or the accelerator is pressed. The technology relies on another feature which detects when the car is not moving or when it is out of gear.<\/p>\n 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.<\/p>\n For drivers using this feature, fuel economy could increase by up to 12 percent.<\/p>\n 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.<\/p>\n Rule 123 of The Highway Code looks at \u201cthe driver and the environment\u201d. 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.<\/p>\n 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.<\/p>\n Around half of this is believed to be from personal vehicles which create around 30 million tonnes of CO2 every year just from idling.<\/p>\n A study by the 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.<\/p>\n The emissions-lowering capability of stop-start systems is particularly important in towns and cities, where traffic is likely to be stationary for longer.<\/p>\n
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