Tacoma Oxygen Sensor Issue

Whoa, that's a bummer! Check engine lights are never fun. A faulty oxygen sensor could definitely mess with your fuel efficiency and trigger that light. Given the mileage, it might just be time for a replacement. But before you jump to that, are you sure about the cable and plug connection? Sometimes a loose or corroded connection can throw everything off. Have you tried cleaning the contacts? What's the air-fuel ratio looking like? Could you give us more details about that?

I checked the cable and plug, but it's still happening. I don't have the tools to check the air-fuel ratio. Could a bad cable or plug cause the oxygen sensor error and worse fuel economy, or is it something bigger? Should I replace the sensor, or get it diagnosed?

Okay, if you've checked the connections and you're still seeing those symptoms, and especially if you can't check the air-fuel ratio yourself, I'd highly recommend taking it to a trusted workshop. They have the tools to properly diagnose everything. It could still be the sensor itself, but it's better to be sure before you start throwing parts at it. You don't want to end up replacing the sensor only to find out it was something else all along!

I took it to a workshop, and they said the oxygen sensor was bad because of a defective cable connection. It cost 95€ for parts and labor. The check engine light is off, and my fuel economy is back to normal. Thanks for the help.