E Klasse oxygen sensor issue

I had a similar issue with my E Klasse. An aged oxygen sensor will trigger the check engine light and impact fuel efficiency. The oxygen sensor, also known as the O2 sensor, monitors the exhaust gases to ensure the catalytic converter is working properly. It's a crucial part of car maintenance. Did the error code specify which sensor? There are usually a few. Also, have you checked the wiring and connections to the sensor? A faulty connection is a common culprit.

Thanks for the quick reply! The error code wasn't specific, just mentioned the oxygen sensor. I haven't checked the wiring yet. Where exactly should I be looking? Is it easy to spot a defective cable?

Without a specific code, it's harder to pinpoint. The oxygen sensors are located in the exhaust system, before and after the catalytic converter. Visually inspect the wires leading to the sensor for any breaks, frays, or corrosion. Also check the plug connection itself; sometimes they get loose or corroded. However, if you're not comfortable working on the exhaust system, it might be best to take it to a workshop. They can diagnose the specific sensor and check the wiring properly. It shouldn't be too expensive if it's just a connection issue or a single O2 sensor replacement.

Thanks a lot for your help! I checked the cable and the plug and it was indeed the problem. I cleaned everything up and the error is gone for now. It cost me 95€ in the end. I really appreciate the advice!