To check if your Focus RS is affected go here and enter your VIN.
http://www.etis.ford.com/vehicleRegSelector.do
Ford is owning up to issues involving faulty head gaskets in the 2.3-liter EcoBoost inline four-cylinder engines found in 2016 and 2017 Focus RS models and is offering to replace them free of charge.
Complaints about the issue have raged for almost a year on a Focus RS online forum and for months on Reddit. In letters that the automaker plans to send to owners this week, Ford is offering to pressure-test Focus RS cooling systems and inspect the combustion chamber for coolant at dealers free of charge. They'll replace the cylinder head gasket and, if necessary, the cylinder head assembly.
http://www.etis.ford.com/vehicleRegSelector.do

Ford is owning up to issues involving faulty head gaskets in the 2.3-liter EcoBoost inline four-cylinder engines found in 2016 and 2017 Focus RS models and is offering to replace them free of charge.
Complaints about the issue have raged for almost a year on a Focus RS online forum and for months on Reddit. In letters that the automaker plans to send to owners this week, Ford is offering to pressure-test Focus RS cooling systems and inspect the combustion chamber for coolant at dealers free of charge. They'll replace the cylinder head gasket and, if necessary, the cylinder head assembly.