GLS Oxygen Sensor Problems

This sounds familiar. My GLS had the same symptoms: oxygen sensor heater malfunction, check engine light, and increased fuel consumption. Have you tested the sensor, specifically the heater element's resistance? Check the air-fuel ratio; deviations may provide insight into the sensor's operation. The problem might not be the sensor itself, but other components. Consider a defective relay or a compromised section of the wiring harness.

Thanks for the quick reply. I haven't checked the heater element resistance yet. Where is the oxygen sensor located in the GLS? Is it easy to reach the cable and plug?

The sensor's location is challenging. Access isn't great, requiring dexterity and specialized tools. I'd recommend taking it to a qualified workshop. The cost might seem high, but a misdiagnosis or improper repair could be worse. My repair cost around 95€. The peace of mind from professional work was worth it. They fixed the problem.

Thanks for the advice. I'll take it to a workshop. It sounds like too much trouble to do myself. Thanks again.