But the industry says it is making huge strides to ensure the complaints that are made are few and far between.
One of the most important initiatives in recent years is the CarWise scheme, headed up by the Retail Motor Industry Federation.
The RMI CarWise Code is the brand name for the new Code of Practice for the retail motor sector, governing car sales, servicing and repair, including bodyshops.
It has been given a branded identity to help the trade distinguish it from other Codes of Practice, as well as to help identify it to consumers.
It will be part of a national Government-backed scheme comprising of Office of Fair Trading (OFT) endorsed codes of practice for industries including the motor industry, building services, travel industry and estate agents. The RMI has set up the scheme for the sector.
RMI chief executive Matthew Carrington said: 'In 2002, the DTI set up a working group to investigate ways of improving standards of service and repair in the motor industry.
'A mystery shopping exercise was performed to find out what kind of customer care was being offered. Unfortunately, the results showed our sector in a poor light.
'The retail motor sector has worked hard to attain a good reputation with consumers, but the results showed that unless we continued this work, and perhaps formalised it, we could risk losing all that has been achieved.
'It was concluded that a number of core customer service standards needed to be adopted. These included areas such as quotes and estimates, preparation of work, completion of work, communication with customers and quality assurance.'
The Working Group agreed that the best way to begin ensuring these core standards are adopted and practised by the sector was for the RMI, along with the Scottish Motor Trade Association (SMTA), to incorporate them into their existing joint code of practice and to actively audit members to ensure their compliance. Once achieved, approval of this revised code could be sought under the new OFT Approved Code of Practice regime.
This is how the RMI CarWise Code came into being and was adopted as the new code of practice for the RMI in October 2003.
Adherence to RMI CarWise is now an RMI condition of membership. RMI members each received a CarWise pack at the end of 2003, which contained an explanation of the scheme.
Carrington said: 'The difference between the new code and the old one is not great. However, the new code is accompanied by a system for checking that members are complying with requirements.'
Minor non-compliance by member garages will be resolved quickly and informally with appropriate guidance and coaching. More serious breaches, or persistent minor breaches of the code, may result in a member being called before an independent disciplinary committee which may expel the member from participation in the code, and therefore from RMI membership.
Businesses that are members of RMI CarWise will be immediately distinguishable by the logo.
Complaints from consumers will be dealt with by the RMI's existing conciliation service, and independent arbitration procedures.