Black smoke and loss of power in 2009 Renault Master: Possible defect in boost pressure sensor?

Hello, I had exactly the same experience with my Renault Trafic from 2012. In my case it was a defect in the waste gate valve. Your car has similar symptoms to mine back then, definitely seems to have something to do with the turbocharger. Firstly, the black smoke, hissing noise and jerking when accelerating are clear signs that the waste gate valve is worn. The vibrations at idle could also indicate this. Secondly, your engine performance is decreasing because the turbocharger cannot develop its full potential and the boost pressure sensor probably also has something to do with the waste gate valve. They replaced the valve in my car at the garage and it's been running smoothly ever since. It was definitely a serious matter that should not be ignored. Your car may also need a similar repair. Hope this helps you!

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Hey there, that really sounds like the same problem I had with my Master. Your tip about the waste gate valve sounds very plausible to me. However, another question has occurred to me: Do you happen to remember how deep you had to dig into your pocket to change the valve back then? And did anything else occur afterwards or did everything run smoothly again? It would be great if you could remember! Thank you for your help!

(Translated from German)

Jo, I still remember it pretty well. It cost me €860 to repair the waste gate valve back then. It was quite a lot of money, but I haven't had any problems with it since. And about the boost pressure sensor: your assumption was correct. After the mechanic had looked at the car, he discovered that the boost pressure sensor was also faulty. This was fixed straight away and the turbo has been running like a champ ever since. So if your car has the same faults, I would advise you to have it checked and repaired straight away. It may cost a bit, but then you'll have peace of mind and won't have to worry about it any more. Hope that helps you!

(Translated from German)

Thank you very much for your detailed reply! I'm reassured to know that it's probably nothing more serious and that I wasn't too far off the mark with my assumption. I will take my Master in for repairs as soon as possible and see what happens next. I have to admit that it hurts a little to put so much money on the table, but when I have a good running car again, it will certainly be worth it. Thanks again for your help and experience!

(Translated from German)