My type r's stock o2 sensor is plugged into a remote display. The car has a cell, with aftermarket pump, The engine control is a Hondata 300 system. My display will show complete lean condition about 5 minutes into a session, generally coming back to normal on the drive into the pits. I am not seeing any change in performance and it seems to have been this way for a year. The plugs looks fine. The tank is properly vented. I have a filter on the fuel pump inlet, it seems to be clear. Any ideas? Is this possibly a failure mode of the sensor?

Of 15 years of running o2 displays, this is the first time I've seen something like this......