Scotty,
I am going to change my spark plugs at the 75,00 mile interval and am using Iridium Toyota replacements plugs. I keep getting conflicting answers as to whether to change the gap or leave the factory settings. They are about .35 and the Corolla I have calls for .41. Should i leave them as is or risk damaging the center electrode by enlarging the gap? Love the show and thanks.
See here: https://www.toyota.com/toyota-owners-theme/pdf/09_SparkPlugs2015_final [1].pdf
Scroll down to your year Corolla and Engine option. Are you using the OEM part called out in that link?
In the lower left corner legend the ** next to any spark plug number indicates to reset gap to original configuration. But your year Corolla is not included.
You are right....have the right plugs...will use the factory plug mfg setting.