Peugeot 108 Serpentine Belt Tensioner Issue

I had a similar problem with my old Opel Corsa. The serpentine belt started acting up, and it turned out to be a faulty tensioner. Does the belt look like it's riding correctly on all the pulleys? And, is the noise constant or intermittent?

The belt's alignment seems generally correct, although the handover action is distinctly absent. The noise is sporadic, more frequent during engine deceleration. Could this intermittent behavior still suggest a primary issue with the tensioner rather than a bearing within the alternator or other driven component?

Yes, intermittent issues like that were exactly what I observed before replacing the assembly. It's likely a tensioner issue and I would recommend that you have the car looked over at a shop before it goes entirely.

Your advice proved invaluable! Following your recommendation, I consulted a trusted workshop. Indeed, the diagnosis confirmed a defective belt tensioner, necessitating replacement. The total expenditure amounted to 455€. The serpentine belt system now functions flawlessly, and the engine's performance has been fully restored. I extend my sincere gratitude for your assistance in resolving this matter.