1998 Grand Marquis Misfire

Hi all first post. I was driving my 98 mgm at highway speeds and had what i believe was a misfire. The car started to gallup and the check engine light blinked a few times. i let off the gas and the car returned to normal operating condition. i drove it home without another misfire. car has 106k miles. it was sitting for about 1 year before i bought it. Maintenence already performed: upper and lower ball joints, oil change, power steering fluuid change, air filter, fuel filter, transmission pan drop/ cleaned and refilled, transmission filter, oil pressure switch.

the guy i bought it from said he changed the plugs within the year.

any ideas what i should do next?

Thanks,
Keith