Verso exhaust temperature sensor issue

Indeed, the symptoms you describe do align with a failing exhaust temperature sensor. Have you noticed any unusual temperature fluctuations, especially around the exhaust components?

Fluctuations? I haven't checked anything myself. Where should I look for them?

Given your lack of familiarity with the exhaust system, I strongly recommend against attempting a self-diagnosis. A faulty exhaust temperature sensor, often triggered by a leak in the exhaust system, can lead to significant performance degradation and potential catalytic converter damage. It would be prudent to consult a qualified mechanic for a comprehensive inspection.

Thanks, I'll take it to a workshop. The sensor was indeed faulty, caused by a small exhaust leak. The total repair cost came to 265€.