Primastar Oxygen Sensor Error

Hey, I had similar issues with my Primastar! Check engine light and increased fuel consumption drove me nuts. I'd bet on the oxygen sensor, especially if it's the original one. Before replacing it, did you inspect the catalytic converter?

Thank you for the quick reply! I have not checked the catalytic converter yet, but I will do so. Can a faulty catalytic converter trigger the oxygen sensor error even if the sensor itself is the root cause?

Yes, absolutely. A clogged or damaged catalytic converter can cause back pressure, which affects the oxygen sensor readings. In my case, the catalytic converter was fine, but the exhaust sensor was gone. I'd advise getting it checked by a workshop, they will know how to solve the problem.

Thank you for the clarification and advice! I took it to the workshop, and you were right - it was the aged oxygen sensor, and the mechanic confirmed the cable was corroded. They replaced the sensor, and the check engine light is gone, and fuel consumption is back to normal. Total cost: 95€.