Spotting if a car's odometer has been tampered with is possible - but not easy.
Vehicle clocking - reducing a car's recorded mileage to increase its value - is widespread. Some reports indicate that as many as 30 per cent of used cars have had their odometers tampered with, although according to one British company that uses a database of 82 million used car mileages, the true figure is around one-in-10.
In Ireland there is no national database of vehicle mileage so it is impossible to cross-check a vehicle's mileage.
The National Car Test service does record a vehicle's mileage at every test but it will not share that information, even with a dealer or private buyer looking to check the mileage of a questionable car.
Although some of the country's main motor dealers have now come together to tackle the problem by creating a database of used vehicle histories, the database is not yet available.
As a result, private used car buyers and motor dealers are left with only their common sense and detective skills to ascertain whether a car has been clocked.
Adjusting a car's odometer is not illegal, but selling that vehicle knowing that it has a false mileage reading is.
At least €50 can be added to the value of a car for every 1,000 miles knocked off a standard saloon and much more can be made if a high-mileage executive saloon becomes a low-mileage model.
The practice used to involve a man with a drill and a few hours in a backstreet lock-up. Today it can be done with a handheld diagnostic tool, often referred to as a speedometer corrector or an odometer recalibrator, which is plugged into the car's diagnostic connection and, within seconds, can wipe thousands of miles, or increasingly kilometres, off the clock.
Ironically, since the motor industry tried to tackle clocking by introducing digital odometers, the practice has actually become easier, as one advertisement for an odometer recalibrator, which is available over the internet, explains: "Our Diga-Consult is a speedometer programming computer for odometer recalibration - it is a single, handy programmer which even the layman without previous experience can operate easily and safely (no extra PC or laptop needed)."
Criminals need not even invest in their own recalibrator, which can cost in excess of €1,000. Instead, they can use clockers who advertise their services in the classified adverts of motoring magazines for as little as €100 per vehicle.
Until a mileage checking service becomes available in Ireland, used car buyers are advised to remain extremely vigilant and to be as sure as they can be about a car's history before they pay. Tips include checking the vehicle's general appearance to make sure it is in keeping with the amount of miles or kilometres on the readout.
Look out for wear and tear, particularly on pedal rubbers, steering wheel and driver's seat. If they are worn and yet the car is reported to have covered only a few thousand miles, walk away. Be even more suspicious if they have all been replaced.
With older vehicles, look for tampering or holes in the instrument cluster or misaligned odometer numbers.
On newer vehicles with digital odometers, there will be no evidence of tampering, so check the vehicle's service history, even going as far as calling the previous owner.
Reputable garages will have no problem passing on a previous owner's contact details. Also look for and identify the garage's stamp in the service manual and then call the garage's service department.
Garages will have the car's recorded mileage at its last service in their records.
If the car is quite old but clean, well-maintained and with a low mileage but has no service history, be suspicious.
Few motorists will care for their car but fail to have it serviced and have receipts and a service book that details their car's service history.
If you are planning to import a vehicle from the UK, it is recommended that you avail of a vehicle history checking service such as that offered by HPI. Similar to how the Experian project will work in Ireland when it becomes available, the HPI service, which can cost as little as £40 (€60), enables car buyers to check details about a vehicle such as if it is reported stolen, is an insurance write-off or has outstanding finance. It also checks with Britain's National Mileage Register, which holds over 82 million mileage readings and receives over 5,000 mileage checks per day, to ascertain whether the car has been clocked.
If you are buying a car in Ireland, consider using a reputable dealer: if the car has been clocked and is unknowingly sold to you, you will have a come back with a reputable dealer, you will not if you buy it through the small ads.