Ok so I've owned this car since new and for better or for worse I've never had and problems I couldn't solve on my own. Anyways I'm having a misfire on cylinder 4 I believe the code said. So I do the usual start with the cheaper simple fix work your way up untill problems solved. So I replace plugs just replaced with oem replacement ngks. Great problem solved so I thought, shortly after boom same misfire. Okay coil is bad so got it, cars got 111,xxx miles on it replace all four. Okay change spark plugs again while I'm here I had one plug that was orangeish burnt looking on the porcelain just above the threads. And now I'm also interested in using a better plug since i'm here working on it. So I see copper plugs run good ( just dont last as long) did my research found a champion eveyone was liking off this forum site from yrs ago. Switched to it went with the gap they were liking. Well anyways I'm having a misfire again days after replacing everything! I can only imagine it's the same cylinder. I'm going to get it checked today but wanted to get this discussion going.