The perception that the motor trade is not to be trusted is still strong among British motorists, a new survey says.

Two in five motorists who take their car in for a service distrust the advice given by their mechanic.

In the last two years, as a result, nearly a third of car owners have changed their garage or mechanic, the survey said.

The findings confirm a recent mystery shopping exercise by officials at the Department of Trade and Industry.

It found that more than half of garages were delivering low standards of service to consumers.

Poor service

Jonny Bewsher, managing director of Drive 24-7, which commissioned the survey, said: "The servicing market is unregulated and there is a real need to raise awareness and provide reliable and consistent standards.

"There are more than a million complaints about car servicing in the UK each year.

"If levels of dissatisfaction with UK retailing were at this level there would be outrage."

Good garage scheme

The DTI estimates that garage overcharging and carrying out sub-standard work costs UK motorists more than �100m a year. UK motorists spend �9bn a year on car repairs.

Over half the 207 garages visited by the DTI inspectors were deemed to have provided unacceptable levels of service.

The industry has agreed to a Good Garage scheme.

The scheme will set out minimum standards that garages have to adhere to.

However, the Good Garage scheme will be voluntary.