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Petrol v Diesel

When you are thinking about buying a new car, before considering various makes and models, the most important thing to consider first is, what kind of engine it will have: petrol or diesel? The best choice will most likely depend on your situation and personal preference in terms of budget, economy and performance.

In the past it was easy to make the decision between types of fuel and engine, but recently, due to technological advances in engine design, the lines have blurred somewhat.

It used to be a straight forward decision, as diesel motors were always viewed as being rougher, stronger and the most economical with petrol engines being the choice for cars and diesel for commercial haulage vehicles.

The fact is that diesel isn’t necessarily the most economical and petrol doesn’t necessarily mean the best in terms of performance. It really does depend on your personal preference along with your budget and the kind of driving you will be doing.

In terms of preference in driving – diesel no longer means boring. Things have changed a lot in the last decade; due to engineering advancements, diesel powered cars can be just as much fun to drive as petrol.

The main attraction of diesel is the torque that diesel engines offer allows for faster, earlier gear changes at lower revs, which can represent a problem for some drivers, but it does mean superb performance with automatic gearboxes.

A modern diesel engine can offer very smooth performance, especially with modern town cars with 2 or 3 cylinder engines. The fuel economy and efficiency figures for these cars have to be seen to be believed, you can expect up to 35% efficiency which totally beats petrol units that are struggling to make 27%.

However, modern petrol engines are becoming more like diesels in terms of their torque, and modern diesel engines are beginning to look more like petrol engines in terms of their performance and pickup.

Modern petrol engines are becoming increasingly light, small and fuel- efficient, with increasingly impressive performance, making the choice even harder. To make things even more confusing, we now have manufacturers offering diesel or petrol electric hybrids.

The next factor to take into account is economy –

UK refineries have been concentrating more on petrol production recently and this has had an effect on relative prices for both fuels. Diesel is simply more expensive in the UK compared to the rest of Europe, then there’s the UK’s CO2 tax to throw into the mix.

Although a petrol engine car might be capable of delivering up to 27% lower fuel economy that a diesel unit of comparable size, the diesel can still be cheaper to run over the course of 2-3 years.

It is possible that the UK government is going to increase taxation on diesel in the near future due to it having 10% more energy than petrol.

When it comes to manufacturers’ quoted MPG figures for various cars and their engines, you have to take into account the fact that these figures have been obtained in laboratories rather than in the field, so its not wise to take them too seriously.

So, what are the differences in running costs when comparing diesel and petrol engine cars? The factors to consider are; price of purchase (always a major factor in decision making) depreciation, servicing costs and insurance along with fuel costs.

Petrol engine cars are usually considerably cheaper than the equivalent diesel engine vehicles. Although diesel cars tend to be cheaper to insure, they are more expensive to purchase, their servicing costs are higher, and can prove incredibly expensive when they go wrong.

When it comes to fuel costs, it really depends on the type of driving the owner has, the number of miles they clock up; overall, the more miles you drive, the more you save in fuel costs on a diesel car compared to the equivalent in petrol.

This has to be factored against the higher cost of buying a diesel car, the cost of diesel fuel injection components and the higher servicing costs. When looking at fuel economy alone, you need to be covering well over 100,000 miles before the diesel car will start to save you any money to offset the difference in purchase price.

Overall, for around town and short journeys, you are better off buying a petrol or petrol-electric hybrid car in just about every respect in comparison to a diesel. However, if you are doing a lot of motorway driving and over long distances regularly, then diesel has a lot to offer, but petrol engines are catching up and so the savings in running costs are not as pronounced and, in the future, diesel will be more expensive to run than petrol so the advantages of diesel over petrol are diminishing over time.