There is a magnetic field around the wire. I am talking about straight wires as you would use for the ign coil primary. These do not make an inductor, because the wires are not wrapped in a loop or coil. The mag field as such does nothing, just sits there. If another length of wire is close to & parallel to the first wire, inductance will be induced [ mutual inductance ] into the wires; in this case, the tiny amount is not going to affect spark output. If the wires are separated slightly, there will be no induced inductance because of the increased distance.
