are 4 cylinder turbos reliable
April 2018 Consumer Reports says Engine Major, Engine Minor, and Engine Cooling are all much better than average reliability for 2016 and 2017.
Make sure in addition to taking care of all regularly scheduled maintenance that you are changing the oil on time and using the properly specified oil (likely synthetic). A lot of reliability, too, will depend on how you drive it. If you drive it hard and power the turbo all the time, you’re vehicle will not last as long as someone who drives it gently and only utilizes the turbo as needed
One thing I’ve read about Ford Ecoboost (turbo) V6 engines is that the oil takes a long time to drain back into the pan when the engine is shutoff. I don’t know if that applies to the 4 cylinder versions. Just check it first thing in the morning (before driving) and you’ll be fine.
I don’t have any specific knowledge on that vehicle’s reliability, but the turbo unit doesn’t make the rest of the engine any more reliable, so common sense says an engine with a turbo will generally be less reliable than without, given the turbo is one more thing that can break. So if your goal is the ultimate in reliability, seek out a non turbo equipped car. But if your goal is improved drivability (acceleration etc) combined with good mpg, I expect Ford’s turbo option should serve you pretty well. Good idea to see what Consumer Reports says about it in their recently published new car guide.
No one really knows how reliable any 2018 car is. It takes 10 years to find out.