Fuel Saving & Economy Reduce Consumption

What's most likely to increase fuel consumption?

Q: What's most likely to increase fuel consumption?

Aggressive driving — harsh acceleration, heavy braking, and excessive speed — is the biggest cause of increased fuel consumption. Under-inflated tyres, unnecessary weight, a poorly serviced engine, and excessive idling also add significantly to how much fuel your car uses.

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Aggressive driving is the single biggest factor that increases fuel consumption, but under-inflated tyres, excess weight, and unnecessary idling all add up significantly. Understanding these causes is the first step to cutting your fuel bills.

Driving Behaviour

Harsh acceleration and braking: Accelerating aggressively and then braking hard wastes the energy you've already burned. Smooth, progressive acceleration and anticipating traffic ahead can improve fuel economy by up to 30%. 3

Excessive speed: Aerodynamic drag rises sharply above 60 mph. Driving at 70 mph uses roughly 9% more fuel than at 60 mph, and up to 25% more than at 50 mph. 2

High engine revs: Keeping revs high by staying in lower gears burns significantly more fuel. Changing up early and driving in the highest gear appropriate for the road reduces consumption. 5

Vehicle Condition

Under-inflated tyres: Tyres that are even 8 psi below the recommended pressure can increase fuel consumption by around 2–3%. Check pressures monthly and before long journeys. 4

Poorly serviced engine: A dirty air filter, old spark plugs, or degraded engine oil all force the engine to work harder. Keeping your car serviced to manufacturer intervals maintains optimal fuel efficiency. 2

Unnecessary weight: An extra 50 kg in your boot increases fuel consumption by around 1–2%. Remove roof boxes, bike racks, and heavy items from the boot when you don't need them. 3

Avoidable Habits

Excessive idling: Leaving your engine running while stationary burns fuel for zero distance covered. Switching off if you expect to wait more than 60 seconds saves measurable amounts. 5

Air conditioning overuse: Running air conditioning at low speeds increases fuel consumption by up to 10%. Use it on faster roads where the aerodynamic cost of open windows outweighs the AC penalty. 4

Short cold-start journeys: Engines are far less efficient when cold. Combining short trips or waiting until the engine is warm for the longest leg of a journey reduces wasted fuel. 2

Reducing the Cost of What You Do Use

Tackle habits one at a time: Addressing even two or three of the factors above — smoother driving, correct tyre pressure, and less AC — can realistically cut your fuel spend by 10–15% without changing your routes.

Pay less per litre at the pump: Once you've cut consumption, make sure you're buying fuel at the cheapest station nearby. CheckFuelPrices shows live petrol and diesel prices at 4,000+ UK stations updated every 30 minutes. 1