AUDI is to seek further details of a survey which for the second time in succession has shown its cars to be the most expensive of the most popular brands to repair. The latest of the six-monthly surveys by Motor Warranty Direct shows that annual repair bills for prestige brands such as Audi and BMW are among the highest, even though in other research they have been shown to break down less often.

Annual repair bills for an Audi and a BMW are likely to about three times as much as that of a Fiat, according to Motor Warranty Direct. Its performance index is based on the average cost per policy, and its results vary drastically between models. Topping the chart with the lowest annual repair cost is Fiat at £43, followed by Mazda (£71) and Ford (£81). Bringing up the rear in the list of 18 manufacturers is Audi (£143), beaten by Renault (£129) and Citroen (£128).

The study took account of the frequency of breakdowns and the cost of parts, including both mechanical and electrical faults, but not wear and tear. The average cost of repair is £106. A spokeswoman for Audi said: 'We are always working hard to manage our parts prices to ensure they are competitive and we will be asking Motor Warranty Direct to give further details on the criteria by which it reached these conclusions. Without them it is not possible to make a constructive comment.'