Helpdesk

THIS WEEK:sourcing petrol cars

From MF: I agree with the letter from SD last week concerning the difficulty in sourcing petrol cars. Every car salesperson in the country is only interested in promoting diesel models.

An acquaintance of mine who does less than 10,000km per year, mainly involving short journeys, has just been persuaded to buy a diesel even though his driving requirements are totally unsuited to this engine type.

Modern diesels require a long time to warm to efficient operating temperatures. This is especially important with the widespread use of diesel particulate filters, used to reduce emissions. If adequate temperatures are not regularly reached, then DPF failure is more likely. This can be very costly. Many modern diesels also have a dual-mass flywheel as part of the clutch mechanism that can be prone to premature failure and expensive replacement.

Turbos fitted to modern diesels are in some cases a further fragile component in a diesel engine. Often servicing is more costly for a diesel than for an equivalent petrol. Insurance can also be more costly if based on engine size. Finally, the tax rate based on emissions is certain to change as the Government is losing too much revenue.

As we said last week, diesel is not the best option for most short-hop urban motorists.

Take the likes of the VW Golf Trendline five-door. You can get a 1.2-litre petrol or a 1.6-litre diesel. The petrol incurs a motor tax bill of €225, the diesel €160. The petrol has a fuel economy figure of 5.5 L/100km, the diesel 4.5 L/100km. Let’s say you do 10,000km a year and taking petrol at €1.63 a litre and diesel at €1.58. This will mean a fuel cost saving of €185.50 by opting for the diesel. A further €65 is saved in motor tax.

The total saving made by the diesel here then is €250.50 a year. However the price difference is €2,245, so on fuel and tax alone it will take you nine years to recoup the initial difference.

Now add in the various other extra costs that might be incurred, such as those you mention. For example, if the DPF needs replacing the bill is likely to exceed €1,000. At that rate diesel simply doesn’t make economic sense. Buyers need to stop and think about their usage and weigh up the costs before choosing diesel.

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