Personal opinion on the 1.6L
Is this a frequent issue with the 1.6 Ecoboost motors found in the Fiesta ST as well? I would try maybe asking some of the Fiesta ST forums and see what their experiences are.
I know this might be off topic but from what I'm aware the Escape with the most miles on here has 107,000 miles and has no issues. The only thing is that it's a 2.0.
Is that the Escape is too heavy for it.
Think about it, the 2.5L specs are very close and it doesn't require the almost constant use of the turbo like the 1.6L does just for normal day to day driving. This means that if your driving is a 50/50 hwy city mix the 1.6L engine has to be run close to it's maximum output over half of it's life.
And if you use the specs for the non-Ecoboost version of the 2.0L used in the Focus you'll notice that it's very close to the 2.5L without the use of a turbo.
I hate to bring up a ghost from the past, but the pre-1974 Pinto's came with both 1.6L and a 2.0L, the 1.6L were known for short lives (strangely enough they were also a Brit designed engine) while the 2.0L were known for having very few problems because they had enough torque to move the vehicle without constantly hitting 4000 RPM.