Engine misfire can be caused by many things. a new set of motorcraft wires might help if testing leads there. Inspecting your plugs can give vital clues. Fuel system tests can be run to verify pressure and volume. inspection of filters and some tests can be tried to be sure they are not dirty or blocked. a system self test is possible with the correct scan tool and test leads.
It is important for your pocketbook not to start guess fixing. sometimes you can end up taking the quality parts off and substituting aftermarket stuff that has a short life. a fuel filter can be checked by removing it and blowing the contents back into a suitable container.
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