GLA Engine Light and Exhaust Smell

I had a similar thing happen with my 2014 Opel Insignia. Engine light, exhaust smell, and rough idle. It turned out to be the catalytic converter, which failed because of an exhaust leak before it. The engine light came on and off at first. Did you see that? Check the exhaust connections before the catalytic converter.

Thanks for the info. You said to check the exhaust connections before the catalytic converter. Can you tell me which connections to check? Besides the smell, what signs of a leak should I look for?

On my Insignia, the leak was obvious around the manifold gasket. Look for soot or corrosion around any exhaust joints before the catalytic converter. But a bad oxygen sensor could also cause those symptoms, so a workshop visit is a good idea.

I took it to a workshop, and they said it was a bad oxygen sensor. The repair, with the sensor and labor, was 375€. The engine runs fine now, and the exhaust smell is gone. Thanks for the help.