Thousands of quality cars could be forced off the road due to the disproportionally high cost of Vehicle Excise Duty, according to vehicle valuation experts CAP.The company recently unveiled the findings of a study that revealed that the cost of taxing some cars that are just seven years old now adds up to a third of their total value.CAP believes the problem stems from 2006, when changes to Vehicle Excise Duty bands were introduced to penalise higher CO2 vehicles. Essentially, this means that cars registered since March 2006, with CO2 emissions between 226 and 225g/km now cost £475 to tax.CAP believes there is a danger that these types of vehicles could quickly become worthless, even though they emit relatively little pollution, because older and less economical cars are generally driven less.To resolve this issue, CAP suggests that lowering VED rates for the top two CO2 brackets after vehicles have reached a certain age, would prevent a number of well-maintained vehicles being sent to the scrap yard.CAP’s car running costs expert, Mark Norman said: “We are now in the crazy situation where perfectly good cars have become uneconomical to own because the cost of taxing them could soon approach half their car’s value.”This means more and more cars will become unsalable and will have to be scrapped long before the end of their useful life.”