At around 64,000 miles mine got a code that said "random misfire" I just did what I can do and changed the spark plugs first. Sure enough I haven't had a problem since. Just something cheap that might work. I had problems with the back right one but it was easily done myself with lots of little extensions. You have to fit them together inside hole to spark plug and then take them apart by using a screw driver down in there to pry extensions apart.
I am supercharged and that is the reason the back right one was difficult.
2001 Ironman Daily Driver... 3.5" suspension lift (OME912 springs and 1" spring spacer), ball joint flip, 1.5" front diff. drop, 33"x12.5 TrXus MT, 16x10 Eagle Alloy rims, Interceptor, PV muffler, K&N air filter, Alpine Supercharger, Bilstein shocks, and some trimming.
2000 Ironman Project LS-1 VX... very slow progress but someday....... ohhhhh someday......