LQ4 243 spark plugs?
Hope there's no lifter or cam damage since its fresh from Saturday. Being its not so constant and every 4-8 seconds I would think a lobe or lifter would be more constant.
After viewing the log little more it is kind of consistent every 4 seconds. I had also changed some idle timing and matching it to the low and high octane tables as part of a walk through to help stop high idle until coming to a complete stop. Tomorrow flash it back to the previous tune and see if it goes away and was something I caused in the tune.

