Citan belt tensioner issue

Sounds like a headache! It does sound like the belt tensioner is the culprit. I had a similar issue on my old Volvo, although the brands are different, the underlying mechanics are often the same. The idler pulley went bad, causing the timing belt to slack and jump. The belt tensioner should keep constant pressure on the timing belt, ensuring smooth operation. If it's failing, you lose that pressure, and the belt can slip, causing all sorts of problems. It's like a bicycle chain that's too loose - it skips and jumps. Have you noticed any unusual noises, like a squealing or chirping, before the belt handover failed completely? If the belt slipped, it could cause catastrophic damage. Has the engine performance decreased?

Thank you for the quick response. I did notice a slight chirping sound for a while before the handover stopped. Regarding the engine performance, I haven't observed any drastic changes, but I'm worried about potential long-term damage. Considering the chirping sound and the failed handover, are you fairly certain it's the belt tensioner, or could it be something else?

The chirping sound is a strong indicator that it is the belt tensioner or one of the pulleys driven by it. Ignoring it could lead to more expensive repairs. It's best to get it checked by a professional who can diagnose the specific issue and prevent further damage. I recommend taking it to a trusted mechanic who can inspect the belt tensioner, idler pulley, and the timing belt itself. They can confirm if the belt handover is indeed defective and recommend the appropriate solution. They will check the engine timing for any signs of damage, and can replace the belt and tensioner as needed.

Thank you for your help and advice. I took the Citan to a mechanic. It turned out to be a defective belt tensioner, just as we suspected. The total repair cost was 455€. I appreciate your insights!