One in ten second-hand cars sold in Ireland has false mileage and one in five imported from the UK has also been "clocked", according to a new survey.

The AA and Cartell, the car checking website, checked over 120,000 cars on the Cartell database, which includes information on write-off data here and in the UK.

The survey says ten percent of second-hand cars for sale in Ireland has a false mileage displayed, while the figure is even worse for cars imported from the UK where nearly one in five has "an unreliable or questionable mileage reading". and AA Ireland examined a random sample of 60,047 vehicle history checks on Irish vehicles carried out recently by potential buyers. Of those checks 11.04% returned mileage discrepancies (6634/60047) – which would each require further investigation to establish if the vehicle had been "clocked" in a given case.

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In addition, a supplementary study which examined a random sample of 64,742 vehicles which displayed at least two mileage readings on the National Mileage Register (NMR), where at least one entry was added in the last 12 months, found that 11.15% of these vehicles had a mileage discrepancy.

The supplementary study also examined a random sample of 13,026 imported vehicles (vehicles which currently display an Irish registration but previously had a UK or Northern Ireland plate) which displayed at least two mileage readings on the NMR and one entry in the last 12 months.

This aspect of the study found that imported vehicles were significantly more likely to have been clocked, with 18.43% of the imported cars assessed as having a mileage discrepancy.

Imported cars had a higher incidence of "clocking"
These results represent a rise in the overall numbers of both domestic and imported vehicles recording a mileage discrepancy since the enactment of legislation criminalising the practice in 2014.

In 2013 the Government reviewed the NCT mileages on 59,528 cars and found that 9.8% of those returned lower mileages on a subsequent test – in other words returned a mileage discrepancy. Those vehicles would have all been at least 4 years old and this may have impacted on the result.

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John Byrne, Legal and Public Relations Manager, said: "Based on an overall study of more than 120,000 vehicles these results are very concerning: on the Irish side we are painting a picture worse than the Government did when they conducted their own research in 2013 when they returned a rate of 9.8%.

"More worrying still is the situation with respect to imports – at 18.43% this rate is alarming.

We would encourage anyone who is importing a vehicle to conduct a vehicle history check before buying and take your time with respect to the purchase of any new vehicle.

Commenting on the report’s findings Conor Faughnan, Director of Consumer Affairs at AA Ireland stated: "Clocking is a very serious issue and something that anyone looking at purchasing a second hand car, whether in Ireland or from the UK, needs to watch out for.

"For example, our teams regularly encounter car breakdowns which can be directly connected back to mileage discrepancies in the car.

"If a car has been clocked it’s highly likely that the car also has a questionable service history so, for example, a motorist could think their car isn’t due a service for another few months but then suddenly find their timing belt has snapped."