2016 crew cab with 14,000miles. This thing has been great till about a month ago. Now I’m getting a stumble under load. I have even had a flashing engine light while going up hill at times. It was in the shop all last week, and they changed a coil pack and plug on number 2 cylinder. It ran great for a couple days, now it’s missing again. Back to ford Monday morning. Anyone had this problem and what was the fix? Thanks!!