With petrol prices spiking again many motorists may be wondering how to cut down on filling up the tank.

1. Make sure your tyres are pumped correctly.

Barack Obama was mocked for suggesting this back when he was running for President in 2008 - but the Automobile Association (AA) has found incorrect tyre pressure uses nearly 8 per cent more petrol than having them pumped the correct amount.

The Motor Trade Association (MTA) recommends checking tyre pressure monthly and before long trips.


Correct pressure varies among tyre and car types, so check your vehicle handbook or online.

2. Try to avoid rush hour

Idling for long periods and constant stopping and starting uses more fuel than a smooth run from A to B.

The AA says turning your engine off if you're stuck in traffic for longer than 30 seconds is better than keeping the car running, and the MTA recommends planning ahead to run errands during off-peak times.

3. Don't speed

According to the MTA, fuel consumption increases by about 6 per cent for every 10km/h faster you go over 90km/h. For most drivers, 100km/h is a good compromise between travel time and fuel economy.

4. Keep your load light

A bag of golf clubs in the boot or a pair of bikes making an unnecessary trip to the supermarket on the roof rack mean more petrol is needed to propel your car around, the AA says. Reduce your load and only take what you need with you.


5. Use your aircon - but only for a little bit

It seems counterintuitive, but opening your windows to cool the car down is actually less fuel efficient than using the air conditioning because it creates drag, the AA says.

However blasting the A/C or leaving the back window demister on after they've done their job is an unnecessary drain on fuel.

6. Take care of your car

Regular services and tune-ups could reduce your fuel consumption by up to four per cent, the MTA says.

The AA puts the numbers even higher, saying a well-maintained car can use 10 to 20 per cent less fuel than one that's badly looked after.

7. Drive smoothly

Don't accelerate aggressively, as this uses more fuel than necessary. Smooth starts and stops help conserve petrol.

8. The simplest way to cut down on petrol costs is to drive less

Short trips to the dairy don't need to be done in the car, and the AA estimates a third of trips in New Zealand are less than 2km long.

Starting your car from cold uses more fuel, so it's more efficient to run all your errands at once if possible.