Community-reported known issues, by make and model.
The Focus ST 250's 2.0 EcoBoost and the smaller 1.6 EcoBoost in other Mk3 Focus models can develop a worn timing chain tensioner, causing a rattle on cold start that clears once oil pressure builds.
Same 1.0 EcoBoost engine as used in the Fiesta of this era: a cracked cylinder head or head gasket failure linked to the coolant system, particularly the plastic coolant elbow near the thermostat housing.
The 1.0 EcoBoost three-cylinder engine is prone to a cracked cylinder head or blown head gasket, usually caused by the coolant system (a thin plastic coolant elbow) failing and allowing the engine to run low on coolant without an obvious warning.