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Have you done a comparative budget on petrol versus petrol car running costs of 2 - 3 litre capacity?

The AA's 2011 official running costs are calculated on ownership of a new vehicle over a 5 year period travelling an average of 14,000km's per year.

It takes into account costs such as; retail prices, interest on outlay, depreciation, registration, insurance, fuel usage plus repairs and maintenance.

To calculate the figures we use the average of a sampling of current new makes/models in a specific engine size category.

The overall operating costs for a diesel vehicle in this engine size are 80.9c/km while the petrol equivalent is 78.1c/km.

As you can see there is very little difference in the two fuels so a lot depends on the negotiated buy price and distance travelled per year. In general, the higher the kilometres travelled per year the bigger the advantage to diesel based on fuel costs and consumption alone.

As diesels get older however the maintenance and repair costs can increase considerably.

Very much a horses for courses decision.