I use DK in every tank. I just think that it was jsut the fuel. I put fuel in it last night and the slight miss has came back. It is not like before, so I am putting my finger on the fuel. The miss is not contant. It seems to be occurring in all cylinders due to watching it shake. There is no stumble, but the power loss is now back. Seems like my pony has a slight limp. They are supposed to change the fuel next week. I sure hope so!