Please help with this log: hesitation issues

[Ninharu]

I have recently been experiencing a confusing problem. I have set my SD tune numerous times without any issues. Recently I just changed my injectors to a set of FIC 1100 hi z's and it ran great for a month. When I am trying to set my initial idle and cruise tune now I have been experiencing issues that I cant seem to resolve. I have attached a log (fuel trims were just reset). Under constant throttle I see dips in my AFRs on my wideband for a second (rich) with no change in throttle position (at 60-90 seconds in the log). It feels like I'm letting off the gas for a second, much like a quick hesitation. It does it for a second and then resumes to the normal 14.7. As well when I am driving, off throttle runs super rich for a few seconds (12s) instead of (18s) where it should be. It also feels like the car is hesitating when in gear and off throttle. Would this be my front O2 sensor malfunctioning? Should I replace it? Or should I be looking at something else?

Any help with this situation would be greatly appreciated as my car is drivable but seems to be getting worse.