i am trying to trouble shoot i pilot ingntion problem on a rheem rooftop unit . its only about 6 yrs old.it has the spark type ingnition .i went through a series of trouble shooting but i could use some help .i will try to explain what i did thus far. one cleaned contact surface whare igniter mounts ohmed for continuity ok . two ohmed whire led from coil to igniter fine. three removed wire led from spark assembly and held it about 3/8 of inch from frame of unit and produced a continious spark four ohmed igniter assembly it self fine .five bought a new igniter no results .