Hello, I am John, a Ford dealer technician.
I hope I can help solve your problem quickly and accruately.
First off you need to have it scanned. Usually autozone or advance will scan for free. This should give you a code that shows which cylinder is skipping. Replace the coil that is skipping. To keep this from happening again, replace all the plugs with motorcraft plugs and replace all the coil boots. The plugs get a larger gap over time and this puts stress on the coil and causes them to fail. The boots are a good preventive measure to keep the coil from arching. Very rarely when I replace all the plugs and boots do I have a repeat repair from a coil going bad.
I hope this answer has been helpful to you! If you have any further questions please feel free to ask.
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