XC90 Jerking and Exhaust Fume Issue

Sounds familiar. I had a similar issue with my XC90. Symptoms were much the same: Jerking, check engine light, rough running. Have you noticed any reduction in engine power or the engine stalling at idle? I'd check your intake manifold pressure.

Yes, actually, there has been reduced engine power, and it did stall once when I was stopped at a light. What was the issue when you experienced these?

Okay, that seals it. My mechanic told me it was the intake manifold leaking, likely due to scorching. You should get it checked professionally; it's quite hard to diagnose properly. You'll likely need a new intake manifold and potentially a new sensor.

Thanks for the advice. I took it to the shop, and they confirmed it was a defective intake manifold. Quoted me 1180€ for the repair. Hopefully, this fixes everything. Thanks again!