[FR-S2GT86]

Testing the oxygen sensor in the way described in that video doesn't tell you whether or not it's within it's calibration. Hopefully it is.

Thoroughly cleaning your stock port injectors couldn't hurt, and would be a good, inexpensive fix if they're indeed fouling up. You should measure the amount of fuel that they flow per minute while watching the spray patterns. They should all be relatively close to each other and within the specifications set by the manufacturer. I believe you can find those values somewhere in a thread here.

I got to looking at your log that you posted the other day while the engine was idling and noticed that you were getting knocking. You should never get knocking while it's idling. That's probably what you are hearing with the engine running in the earlier video you posted. I can understand if you're getting a couple of misfire codes along with the knocking in your logs, but I didn't see any indicating to me that it's not fuel or ignition related, so its possibly mechanically related. You might want to get a hold of the guys that built your engine to show them that video and your logs.

I also noted that the rear 02 sensor was reading 255, I don't know if that's indicating a very rich condition or a very lean condition, but that's the sensor that's located after the catalytic converter, so if it's rich there, AND you're fuel trims are running +22 to +25, then the upstream O2 sensor is telling the ECU that it's running lean and adding more fuel to compensate, which is getting through the catalytic converter where the rear O2 sensor is picking up the rich condition (if that value is indeed indicating a rich condition).