Pressing a switch located inside almost all modern cars could help petrol and diesel owners make major fuel savings.

13:56, Sun, Dec 29, 2024 | UPDATED: 13:57, Sun, Dec 29, 2024

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car button

Motorists can save fuel pressing one key car button (Image: Getty)

Petrol and diesel owners could save fuel by pressing a switch located inside most modern vehicles. 

Activating cruise control on a long stretch of road will keep the vehicle at a “constant speed”. 

Maintaining the same speed is essential to make travel fuel-efficient with constant acceleration and braking using up more petrol and diesel. 

Most brand-new cars will come with a cruise control mode as standard but those with older machines may miss out. 

The tool can be activated by pressing a switch on the car dashboard or may be available through the onboard infotainment system.

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Maintaining speeds can boost fuel-efficiency (Image: Getty)

Breakdown specialists at the RAC said: “Cruise control only aids fuel economy when driving on a constant flat surface, hence why it is usually best reserved for motorway driving.

“One of the keys to saving fuel is driving at a constant speed, cruise control can do this effectively on flat surfaces, making your driving as fuel efficient as possible by negating unnecessary acceleration.”

Motorists with older cars with no access to cruise control can have the part retrofitted by a specialist for around £300 to £500.

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According to the RAC, the most fuel-efficient roads in the country are usually motorways as road users can cruise along in a higher gear.

However, motorists may find the tool uses up more fuel in certain situations such as hilly routes. 

Roads with steep gradients can be a problem for the system meaning it is not advised to just switch on cruise control if fuel consumption is motorists' biggest worry. 

In this situation, balancing the acceleration with a foot may even suck up less petrol or diesel than relying on the software. 

The RAC explained: “This is because your cruise control would be slower to react to gradient changes, meaning when reaching the brow of a hill – at which point you would normally take your foot off the accelerator to maintain more of a constant speed when descending – your cruise control will keep the power on for a little longer as it’s unable to see the gradient change in front of you. 

“Driving in this way regularly would lead to worse fuel consumption.”