car misfiring on 2000 Lincoln Town Car

i have a 2000 lincoln town car that misfire after the engine has been runing for about 10 to 15 minutes i have change the sparks plug and the car still misfires

Asked by for the 2000 Lincoln Town Car
2 answers
The coil boots should be replaced when you change the spark plugs. Did you do that?
i do not know