Seat Tarraco Hybrid Belt Handover Problem

Sounds like a potential belt tensioner issue. I had similar symptoms on my old Renault Megane – the engine performance dipped, and the belt handover wasn't working right. Have you checked the tensioner pulley for any visible wear or damage?

Wear or damage, like what exactly? Is it something I can spot without taking everything apart? You mentioned 'belt handover' not working. Is that like the belt slipping when the engine switches between electric and combustion?

Yeah, exactly like the belt slipping during that transition. On the Megane, I could see the tensioner pulley wobbling and the serpentine belt vibrating excessively. Best bet is to get it to a workshop, they can properly diagnose the belt tensioner and idler pulley.

Huge thanks for the insight! Took it to the shop, and you nailed it. The belt tensioner was indeed the culprit. New tensioner pulley and serpentine belt later, and the Tarraco is purring again. 455€ lighter, but worth it for the peace of mind.