Hi, I am new here. I keep carbon fouling plugs and no mechanic can tell me why. They can't find anything wrong mechanically with the vehicle. It is tuned by ZFG racing and the guy tuning says it isn't running rich. He is taking a break from tuning right now so I thought I might get some help here. It is a 2016 ford edge sport 2.7 ecoboost. I have received my final tune from him and it has went through 3 more sets of plugs. I have been using NGK 95605 plugs and then I tried the motorcraft stock ones with the same results. All plugs are carbon fouled after a few days. It misfires on high rpm occasionally. I assume that is because of the fouled plugs. If it weren't running rich what else would cause all plugs to foul like this?
Thanks for any help.