Volvo V50 exhaust leak symptoms

Sounds familiar. Had a similar issue with my old Peugeot 308. Same symptoms – check engine light and all. Could be a leak in the exhaust system messing with the sensor readings.

A leak? Where exactly should I be looking for this leak, and how would that affect the temp sensor?

A small crack or loose connection anywhere in the exhaust can throw off the readings. The ECU then thinks the exhaust is too hot or cold, triggering the limp mode and extra fuel. Best bet is to get it smoke tested at a workshop.

Smoke test it is. Thanks for the heads-up! Turns out you were spot on. Small crack near the cat. New sensor and a bit of welding, 265€ and I'm back on the road!