A FURIOUS row has broken out over the Vehicle Certification Agency's New Car Fuel Consumption and Emissions booklet after an investigation by Fleet NewsNet's sister print publication Fleet News revealed a string of errors which could cost company car drivers hundreds of pounds.

The Government agency hurriedly altered its website after the errors were pointed out by Fleet News and has promised to issue a list of corrections for the booklet, but 30,000 copies have already been sent to fleets. So far only errors involving Audi and Peugeot vehicles have come to light. But, Fleet News believes there are more and there continues to be major concerns over the complex way some manufacturers - notably Ford and Renault - list the essential carbon dioxide emission figures.

The booklet claims the new Audi A2 1.4 TDI was the first diesel to achieve Euro IV emissions standards. But it was the petrol models that should have been listed as Euro IV, while the diesel was Euro III. All diesels have a controversial 3% tax supplement under the new 2002 carbon dioxide-based company car tax regime, but if they reach Euro IV emission standards, the supplement is removed and could have led to rocketing demand for the model. The A2 1.4-litre diesel produces 116 g/km of CO2, well below the 165g/km/15% starting point for the new tax. For a £16,600 TDI SE A2, the saving between 18% tax and 15% tax would have amounted to £597 over an average three-year lifecycle for a 40% taxpayer. The guide also mistakenly lists a string of Peugeot petrol-engined vehicles as being Euro IV standard.

The VCA said it was at the mercy of manufacturers providing the information for the booklet, but Stewart Whyte, director of the Association of Car Fleet Operators, lambasted both sides, saying they were playing with fleets' finances by not taking the issue seriously enough. He said: 'I continue to be amazed that a Government agency can be so complacent and ignorant of the needs of real fleet customers. There is no reason for a Government agency that is in charge of the approval data to get it so wrong. They have refused to consider that they should tell manufacturers to provide information in a certain way.'

Long-running problems with the guide continue in the latest edition, launched this month, with Ford listing CO2 emission figures according to wheel size of its models, while Renault is listing vehicles according to VIN number rather than model. 'How can you work out what vehicle that applies before you have even bought it t?' Whyte said.

A spokesman for the VCA said information was provided by manufacturers and was taken to be correct at the time. It was only after the guide had been published that uncertainties over emissions figures began to sink in. He said: 'We are taking steps to rectify the problem.'