Hi

My girlfriend and I bought a 02 plate Fiesta (£1950, about 60k miles) from a dealer at the end of November. It came with a 3 month warranty. Within the first week a fault developed whereby the engine management light came on and EAC warning flashed resulting in a loss of power. We contacted the garage and they agreed to take a look at it but in the time between contacting them and taking the car into the garage, all seemed fine, so we agreed with the garage to "see how things go" and take it back in if the problem occurred again.

Unsurprisngly the problem did occur again and the garage ran a diagnostic check revealing an error which they apparently sorted when they finally had a chance to look at the car 2 weeks ago. However, since then the problem is still occurring intermitently. I am planning on taking the car to them tomorrow and refusing to accept it back until they sort it (and are able to prove it by showing a clear diagnostic). Is this reasonable? and perhaps more importantly, where do we stand (given the relatively low value and age of the car) in the event that they are unable to get to the root of the problem and fix the issue?

Any help/advice would be appreciated.