The invention relates to a method for coating spark plug threads with a polytetrafluoroethylene mixture comprising the steps of (a) bringing the spark plug to room temperature of 21° C. to 26° C. (70° F. to 79° F.); (b) mixing the polytetrafluoroethylene mixture thoroughly and filtering the material through a 100-mesh stainless steel screen (0.146 mm openings); (c) applying a minimum dry film thickness of 20 microns to 30 microns (0.8 mil to 1.2 mil) to the spark plug thread; and (d) baking the spark plug for 15 minutes at a metal temperature of 232° C. to 260° C. (450° F. to 500° F.).