Petrol or diesel - which is best?

With fuel prices higher than ever, new car buyers are often tempted to choose diesel automatically, as these are more economical.

However, you pay a premium for a diesel car because they’re more expensive to produce – and you may have to cover tens of thousands of miles before you get that premium back.  Most city cars and superminis are very economical even in petrol form – 55mpg is quite normal for some of the smaller 1-litre city cars. 

Buying a small car with a diesel engine may cost hundreds of pounds more, but it won’t necessarily be that much more economical.  When you consider that diesel is usually more expensive to buy than petrol, it takes even longer to get your money back.

Also, diesel cars are more complex, so more likely to go wrong; modern ones need a regular blast to clean their exhaust filters out, with lots of low-speed driving potentially causing major problems.

Buying a small car with a diesel engine may cost hundreds of pounds more, but it won’t necessarily be that much more economical. 

However, there is something else to consider. When you come to sell your car, if it has a diesel engine it will probably be more saleable, so worth a bit more. Ultimately, you need to work out what the price difference is between the petrol and diesel variants of the car you’re considering buying.

You then need to look at the difference in fuel economy, how many miles a year you typically drive and how long you’ll keep the car. Once you’ve established all those things you can decide which fuel makes the most sense - and the chances are that it won't be diesel.

Your fuel choice should really be between petrol and diesel. Liquid Petroleum Gas is not as widely available as it was, and there are lots of dodgy conversions about.  You might also want to think about a hybrid car, but bear in mind that the fuel consumption figures quoted for these are rarely attained in the real world because of the way the testing is done.

In reality, if the car is driven flat out on the motorway, a hybrid car is no more efficient than a conventional one. You’ll only reap the benefits of a hybrid if you’re using the car in urban or more areas regularly, where you’re braking and accelerating more frequently.