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Sunday 26 March 2023 Dublin: 8°C
# Dear Driver
What counts as 'good' MPG nowadays?
Got a motoring question or looking for some advice? We’re here to help.

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THIS WEEK, A reader asks:

What is ‘good’ MPG these days? What should I expect in a new/second hand car?

Buying a car with decent MPG is always a good idea as it will save on running costs. However, this question is a hard one to give a straightforward answer to as there are so many variables – type and size of vehicle, engine and driving conditions are just the start. In general, diesel cars are more fuel efficient than petrol cars.

The generally accepted standard has risen from a consumption of around 8.1 to 7.1 litres per 100km (35-40mpg) in the past to more like 5.6 to 5.1 litres (50-55mpg). As a rule of thumb, vehicles listed at less than 6.0 litres/100km are considered to have ‘good’ MPG.

Shutterstock / iQoncept Shutterstock / iQoncept / iQoncept

If you’re driving a compact diesel you should expect to see 5.6 litres/100km (50mpg) in daily driving, even if you are in urban traffic a lot. A good down-sized turbo petrol should easily exceed 7.1 litres/100km (40mpg) in real world conditions, while a hybrid should really be getting better than 4.7 litres/100km (60mpg), but you will need to try hard to get that, as much will depend on your driving style.

The current passion for all things SUV has an impact though. You can expect to knock around 5mpg off those averages if you’re driving something tall – especially if the car has four-wheel drive, which means extra weight and more mechanical friction.

When buying a used car try to look for one that has a full service history as engines that have been well looked after tend to be more efficient and will yield better fuel economy figures than neglected engines.

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