Calif-spec Tacoma PreRunner allergic to East Coast gas?

My '03 Tacoma Prerunner V6 has 116K miles and recently lit up its Check Engine light, returning a code for a failed up-stream air/fuel sensor.
I recently drove across country, using many different fuel formulations ranging from CA gas to midwest ethanol to whatever they put in the gas here in the NY-NJ area (a mystery ingredient that seems to turn motorists irate and confuse their horn as a turn signal.)
Anyway- age, or fuel, what killed the sensor? If fuel, will it happen again by time I get back west?
Thanks,
Wil

It ain’t the fuel. It’s just normal age. Occasionally something wears out.

Re: NY/NJ attitudes; that’s just the way New Yorkers and New Jerseyites communicate with one another. No offense intended, they’re just sending normal behavioral signals.

Laid back is a West Coast attitude. You won’t find that on the East Coast.