My bro-in-law 97 Ls has a CEL saying that it's misfiring on cylinder #2, i haven't diagnose it but i just need some quick info of what could be the problem so i can fix it quick, all i did was check for sparks so far and it seems to be good, i'm thinking it could be fuel/injector problem, oh yeah and i just change the headgasket but i don't think that would cause it, the car run strong and fine, any ideas?