Ok4450 your defense of db4690 is commendable. I am assuming that others do not read these forums for the “truth” to cure the ills of their cars or believe knowledgable people actually know what they are talking about. Rather, I hope that people are reading these posts, as I do, to glean ideas of what worked and to discard the pontifications of experts with equal gusto.
Therefore, while I do not claim to be an expert, I must restate my original goal of giving open minded readers another path to explore while troubleshooting their O2 sensor P2231 code.