Civic VX swap code 48. How long to set?

[Carwhisperer]

I've been struggling to get the wiring right in my vx'd obd0 chassis. I'm pretty sure I've got it now but I'm not 100% sure of my connections. I finally got rid of code 48 for a while. I drove for 10 minutes, no codes. Then I parked for 20 minutes and drove again and code 48 came back within a minute. I reset the ECU and drove for 10 minutes. No codes. Parked for 8 minutes, code came back after 2 minutes. Should I expect my O2 sensor at this point? Pretty sure it is a used genuine Honda sensor, no idea how much time is on it. This is a lightly turbo'd d15z1. Kept the boost under 2psi for these drives, no map sensor code.

[Carwhisperer]

More data. Pretty much every time the code doesn't set on the first drive it will set right away on a second drive. But on to the third drive I get no CEL. Mileage has gone way up since before I rewired the o2 but I haven't tested a full tank yet. Also got code 12 on the freeway, egr system, but it didn't come back on after shutting down and restarting. Seems to take a long cruise to set it. I think I can feel lean burn kicking in and out even at times, so I think I'm getting there.