My 2015 X3 had a rotten egg smell and the check engine light came on. A generic garage quoted me a fortune for a new catalytic converter. Then I found a specialist that actually does Catalytic Converter Repair Dubai BMW – they ran a proper diagnostic, confirmed the cat was partially clogged but not melted, and did a chemical cleaning and heat treatment on it. Also replaced a lazy post-cat oxygen sensor. The smell is completely gone, the light stayed off, and the car passed the emissions test easily. Cost was about a third of what a new converter would have been. The mechanic said most people rush to replace, but many cats can be saved if caught early. Really glad I got a second opinion. Highly recommend trying this route first.