Well, it seems that the o2 sensor wiring is good. For the fun of it, i installed a TPS sensor that i got from the junkyard (the sensor that was in there was from NAPA, their top of the line), and swapped out the IAC with a junkyard part, and its idled well for 30 min, no studders or voltage drops. Is it possible with the non OEM TPS sensor, that the readings were just off, leading to a lean fuel mixture causing the o2 sensor to read bad?
I didnt get a chance to test drive it yet (pooring down rain, and i wasnt going to drag an 8 year old kid with me), that will be tomorrow. There was just a slight flutter of the RPMS after about 20 minutes of idling. Is it possible thats just the ECM relearning?