Seeking Advice: Unusual Symptoms in 2017 Volvo S90 Diesel with 144,757 KM

Hey there! Yea, I reckon I've been down that road with my 2014 Volvo V60, petrol. Had these very symptoms, and turns out it was the waste gate valve, just like you suspected. The symptoms lined up - unstable ride, power cuts, the hissing sound – all classic signs. Last time I was at the garage, they had to clear the waste gate duct for starters. It was clogged real bad, causing all these problems. Also, they recalibrated the valve to correct the boost pressure. When it's out of sync, it goes off spinning more than it should, giving you that whistling sound. Yup, it was a serious problem, all right. Let me tell you, I was sweating bullets when I first heard my car whistling like a tea kettle. Also, driving around with this issue for a long time can cause some serious wear and tear on your engine. Get it checked out asap. This isn’t something you can fix with a couple of tools from your garage. But hey, now you know what the problem is, you can head on to your mechanic armed with some knowledge. Don’t let them bamboozle you. Good luck!

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Hey, thanks for the input! It's a relief to know I might be on the right track with this, though the sweat bullets part is relatable for sure. Your experience sounds very similar to what I'm dealing with, probably even the same waste gate valve issue. Do you recall how much it set you back to get fixed at the garage? Also wondering, has any other issue popped up related to this since you got it sorted? Thanks again, you're a lifesaver!

(Translated from German)

Hey! Happy to help. As to your question about the cost, they billed me a solid 860€ to sort out the waste gate valve issue. Not cheap, I know, but it was worth it to get my trusty Volvo back on track. And, since that visit to the mechanic, I haven't had any repeats of the previous problem. Boost pressure's been regular, no more black exhaust smoke or that crazy whistle. Basically, since they fixed that waste gate valve issue, my ride's been running as smooth as a hot knife through butter. Good luck getting your S90 sorted out! If you've got any more questions, just shoot. Here to help!

(Translated from German)

Thanks a ton. Boy, 860 Euro is a bit steep, but what can you do, right? After all, a smooth car ride definitely beats the roadside assistance drama. It's good to hear you've not had further issues. Hopefully, things will pan out for me the same way. I’ll take the Volvo in ASAP, armed with your advice. I'll let you know how it goes. Cheers for being such a solid help! Much appreciated, fella!

(Translated from German)