2003 Mazda Tribute was idling rough when starting from cold. Got to the point where it would even stall when at a stop sign if I didn't let it warm up enough. For a while it never threw any codes so I couldn't figure out what the issue was.
Finally it threw me 2 codes and only 2 codes: P2195 and P2197
O2 Sensor Signal Biased/Stuck Lean Bank 1 Sensor 1
O2 Sensor Signal Biased/Stuck Lean Bank 2 Sensor 1

Sensor 1 on both banks. For reference, I pulled this from my Chilton service manual:
Upstream (front cylinder bank) = Bank 2 Sensor 1
Upstream (rear cylinder bank) = Bank 1 Sensor 1
Downstream (front cylinder bank) = Bank 2 Sensor 2
Downstream (rear cylinder bank) = Bank 1 Sensor 2

Concise version:
Upstream front = B2S1
Upstream rear = B1S1
Downstream front = B2S2
Downstream rear = B1S2

Diagnosis steps:
Cleaned Idle Air Control valve (IAC), cleaned around butterfly plate / valve in the air intake throttle body, cleaned Mass Air Flow (MAF) sensor, sprayed carburetor cleaner around engine bay while idling to check for vacuum leaks; idle did not fluctuate.
Issues only occur when starting engine from cold state and disappears once driven for a few minutes. Therefore, it has something to do with components that operate differently depending on temperature.
I was thinking it might be something like the Engine Coolant Temperature (ECT) sensor, but the O2 sensors also require heating up in order to accurately operate.

Trying to source the O2 sensors now, hopefully it'll fix it.

Update:
The issue was not O2 sensors. Good thing I didn't spend money getting them. Made another thread here:
https://www.mazdaforum.com/forum/maz...gh-stft-52049/