Corsa belt handover issue

I also own a Corsa, though I have the petrol version. I recall a similar thing happening with mine. The symptoms seem aligned with what I experienced. Does the problem occur at certain speeds, or is it all the time?

Good to know I'm not alone! It seems to happen randomly, regardless of speed. Sometimes it's fine for ages, then suddenly it's back. Any thoughts on what it could be exactly? I was thinking about the tensioner pulley or serpentine belt, but I am not sure...

Given the intermittent nature, and your initial thoughts, it's quite likely your belt tensioner is faulty. I'd suggest having it checked by a qualified workshop. I ended up doing the same.

Thanks a lot for the advice! I took it to the workshop, and you were spot on – it was indeed a defective belt tensioner. Repair cost me about 455€. Hopefully this fixes it!