Older versions of the 1.0 EcoBoost engine had a number of reported problems linked to the coolant pipe that was found to have a weak union in it. Most of these pipes should now have been replaced under recall by Ford. However, if a Fiesta has been serviced outside of the dealer network, it's possible there may be a few cars still out there with this problem. You can read more about it here: www.honestjohn.co.uk/carbycar/ford/fiesta-2013/good

The latest Fiesta 1.0 EcoBoost was launched in 2017 and complaints are rare. The engine also uses a timing belt in oil system (sometimes referred to as a 'wetbelt') which means it is designed to last the life of the car.