Hi, I happened to have a similar problem with my 2015 Seat Leon TDI, I wouldn't say I'm a car expert, but I know a little something. At my garage, they eventually put it down to a faulty cable/connector. The repair cost me 95 euros. Have you already read the fault memory and do you know what fault code is displayed? That would help me to help you better.

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Thank you very much for your quick reply. I have had the fault memory read out and it shows fault code P0325. I already suspect it could be due to the wiring/plug connection, as you said. The last time I was in the workshop was 67256 km ago, so it's been a while. Maybe I really should go again. Your tip has definitely helped me!

(Translated from German)

Hey, no problem, always happy to help! The error code P0325 is interesting, this code stands for a defective knock sensor. Sometimes it really is just down to the wiring or the plug connection, as was the case with my car. It would definitely be a good idea to visit a garage and have it checked, especially if it's been a while since you were last there. Even if you have already covered 67256 km since the last service visit, this is not necessarily the case. A faulty knock sensor could definitely cause all the symptoms you have described. Have it checked by a mechanic and let me know what comes up. I'll keep my fingers crossed that it's only a minor problem!

(Translated from German)

Thanks for your advice! I will definitely go to the garage and have it checked. Your words have confirmed my suspicions and shown me that it's really worth having it looked at more closely. And thank you for keeping your fingers crossed for me! I'll definitely keep you posted and let you know what comes out in the end. See you then and thanks again!

(Translated from German)