V90 NOx Catalyst Aging

Interesting. I own a V90 hybrid as well, and I had a similar issue not too long ago. The NOx catalyst can be a real pain. Did you notice any changes in fuel economy or engine performance besides the check engine light and error code?

Fuel economy seems normal, and I haven't felt any performance decrease, but I do smell exhaust fumes more often. What was the fix in your case, and was it costly?

Given the exhaust smell, it does sound like a leak, which accelerates the NOx catalyst aging. For me, the leak was the primary issue causing the error. I would suggest taking it to a trusted workshop for diagnostics to confirm the leak's location and get a proper repair estimate. Ignoring it could lead to further catalyst degradation.

Thanks for the insight! I'll book it in for diagnostics. Turns out it was a small crack in the exhaust manifold, costing 265€ to repair. Hopefully, that's the end of it.