HelloCustomerand thanks for your question.
The most common cause for hesitation/skipping/engine misfire is the ignition coils. This vehicle has 8 of them, one for each cylinder. The problem is determining which one is at fault. If the engine light ever came on then the codes could be read from the computer with a scan tool to determine which one is at fault. If there is no check engine light then about the only way is with a Ford IDS scan tool which can access part of the computer to check misfire history and can also monitor the power balance of the engine in real time so that when it misses (or skips) the correct cylinder can be identified.This scanner can also stress test the coils individually and find bad ones even if the engine is not misfiring at the time of the testing.