Went to start my excursion today drove 3/4 mile everything fine .Shut truck down dropped kids off , went to restart and feels like its missing on multiple cylinders . Checked the code that was thrown and came back as excessive misfires for emission. Checked fuel filter seemed clean and I will change it,drained fuel , started back up and seems fine now. I'm leaving on a 1000 mile trip and in2 days and just a little nervous. What is some things to check ?