Answer
Should still be covered under warranty. you need to book an appointment with a ford dealer with competent ford diesel certified techs employed there. these engines have many problems in them. could be a failed egr cooler, bad injector(s), bad glow plug(s). too many items to list. do you see smoke coming from your exhaust pipe? what colour is it? white= glow plug?(s)? black= injector(s), egr system carboned up, grey= coolant leaking into exhaust, egr cooler bad, head gasket?