Skip to main content
0 items

5 tricks to improve fuel economy

Fuel economy advice

The prices of petrol and diesel at the pumps have never been so high; it now costs at least £100 to fill up the average family car - but if you own a large exec car or SUV you'll be spending a lot more than that if you can face brimming the tank.

How can you reduce your spend on fuel? Maybe you're still working from home, in which case you're already doing a good job of cutting the number of miles you cover.

You could go out and panic-buy an electric car, but that will invariably involve putting down a hefty deposit if you're buying a new car on finance, and the prices of used EVs have skyrocketed as a result of increased demand. In any event, we're hoping that the price of crude oil will begin to fall once the war in Ukraine ends (fingers crossed). 

In the meantime, with your eyes glued to the fuel gauge, frugal fuel consumption can be achieved by simply changing your driving style and performing basic vehicle maintenance. 

Here are our top five ways to keep your fuel habit under control.

1 Show it some love

A badly maintained car can have an unhealthy desire for juice. Dirty air and fuel filters won't help fuel economy or engine performance, while neglecting an oil change can cause premature piston ring wear, thereby reducing engine efficiency. A Haynes Manual can help you look after your car and help you save yet more money by avoiding having the work done at a garage – find your manual here.

Poor wheel alignment is a shortcut to increased tyre wear, rolling resistance and fuel consumption. 

Sticking brake pads are another route to more slow than go, and worn wheel bearings can up friction as well. 

Finally, there's the age-old question of whether supermarket fuel is less efficient than big-brand juice.

The answer is no, as aside from extra engine-cleaning additives, fuels with the same octane ratings will perform identically.

2 Take it easy

Revving out an engine to the max is plainly bad news for fuel economy, yet driving everywhere in a high gear at very low RPM can result in an engine's ECU injecting extra fuel to prevent stalling. As is often the way, balance is best. 

Feel for the sweet spot in each gear where your engine pulls comfortably without labouring, yet isn't revving excessively. 

Once in top gear on the open road, your car will have an optimal speed for best fuel economy. For most five-speed cars, this will usually be between 50 and 60mph.

Vehicles with more gears can increase this slightly, but the extra air resistance at speed means staying below 70mph is a must for fuel-saving.

50mph on car speedometer

3 On a roll

Coasting is a great way to save fuel, but should you stay in gear? Coasting with the clutch down eliminates engine braking, but at the cost of using some fuel to keep it idling. Alternatively, engage a gear and most electronically injected engines will completely cut the fuel supply, though the mechanical drag that's introduced means you won't coast as far. 

The trick is to use both methods, staying in gear while rolling to a stop or descending a hill, and coast with the clutch down for maximum distance.

Once stopped, if you suspect you'll be stationary for more than 10 seconds, switch off your engine and it'll use less fuel restarting than it would if you'd left it idling.

4 Keep ’em closed!

You'll often read fuel economy advice telling you to turn off the air-con and wind down a window, but lowering the glass disrupts the air flow around a car and can have a real impact on a car's mpg. If the sun isn't out and you're not sweltering, by all means switch off the air-con, but modern cars have very efficient compressors that hardly affect fuel economy, especially when you're on the open road.

It's important to use air-con once in a while, though – even during the winter months when you can use the ac with the heater to defog windows – because the system needs to be kept lubricated; if the seals dry out the gas used by the air-con can escape, which will require the system to be regassed. If the seals need to be replaced you'll end up with a bigger bill.

5 Under pressure

Low tyre pressures can noticeably increase fuel consumption. Just think of the increased leg work required to cycle with soft bike tyres. But getting the pressure right isn't as simple as pumping up to the maximum PSI rating moulded on your tyre's sidewall. That's likely to bulge your rubber, lowering grip levels and increasing wear around the central section of the tyre – and will also harm your fuel economy.

Instead, inflate to the pressures listed in your vehicle's handbook. You may also find your car's recommended tyre pressures on a chart on the inside of the fuel filler flap or on the driver's-side B-pillar when you open the door, listed in psi or bar.

Usually (but not always) front tyres require more pressure than rears to compensate for engine weight, although back tyres may need to be pumped higher should you regularly carry heavy luggage. Again, your handbook or the pressure chart should have recommended pressures for a vehicle with normal or high loads.

5 tricks to improve fuel economy
Tags: