I purchased a Second-handa Mazda 6 2004 in October 2010 and have had to take it back to the dealer on three separate occasions, mainly due to noisy engine and excessive fuel consumption.

As we were given a three-month RAC warranty with the car (maximum limit £2k) no costs were incurred by us. After the last time and being told by the dealer that the oil usage was consistent with a car of its age they "checked it over" and topped up the oil. Not satisfied we sought a second opinion (without dismantling) to be told there were potentially serious engine and sump problems.

The main dealer was informed and we returned the car to them to be fixed and we have been told that the amount of the RAC three-month warranty would be disregarded as basically, they check all cars over prior to them being advertised on the forecourt and they didn't know how this one had slipped through the net. We have been advised that in order to fix the car they will need it for a number of weeks but they are unable to offer us a courtesy car, so as a family with three young children this is proving to be extremely inconvenient.

Please can you advise what are rights are with regards to the following:

1. Returning the car to them and having a full refund.
2. How we stand with any future complaints that may arise due to this.
3. Can we insist on a courtesy vehicle whilst our car is undergoing the repair.