BMW X6 Diesel Boost Pressure Issue, Need Help Fast!

Had the exact same symptoms on my 2011 BMW X5 35d last year. Initially thought it was the sensor too, but turned out the connection plug to the boost pressure sensor was corroded and had a loose pin. Experienced the same jerking, whistling, and poor performance issues. The diagnostic showed erratic boost pressure readings. My previous mechanic kept replacing parts without solving the problem. Found a BMW specialist who properly diagnosed it, it wasn't actually the sensor itself but the wiring harness connector. They cleaned the terminals, repaired the pin connection, and sealed it properly. Not a serious repair in terms of parts, but critical for proper engine function. Also had them check the rest of the turbo system while they were at it, everything else was fine. Car's been running perfectly since then, no more engine lights or performance issues. Hope this helps narrow down your problem. Get a proper diagnosis before replacing parts.

Thanks that's really helpful! Your situation sounds identical to what I'm experiencing. I'm actually leaning towards getting it checked by a specialist now rather than risking another wild goose chase. Would you mind sharing roughly how much you ended up paying for the fix? Also, has everything stayed solid since the repair, or have you noticed any other issues pop up? Really appreciate your detailed response!

Hey there! Following up on your questions, yes, absolutely everything has been running smoothly since I got it fixed. I paid exactly 95 € for the repair, which was mainly labor costs for diagnosing and fixing the cable connection to the boost pressure sensor. The mechanic basically found that the wiring was the culprit, not the sensor itself. I'm really glad I went to the specialist, they sorted it right away without trying to sell me unnecessary parts. The car's been performing beautifully since then, no more weird noises or jerky acceleration. Haven't had a single warning light come on, and the fuel consumption is back to normal. If you're seeing the same symptoms I had, I'd definitely recommend getting it checked by someone who knows these engines well. It's such a relief having it properly sorted, and it wasn't nearly as expensive as I'd initially feared. Best decision I made was not letting my previous mechanic keep throwing parts at the problem! Let me know how you get on with yours, sounds like it could be the same issue.

Thanks so much for all the info! Just wanted to update you, I took your advice and went to a BMW specialist yesterday. You were spot on, it turned out to be almost the same issue. The connector was damaged and causing all those problems. The repair cost me a bit more, around 120 €, but honestly, it was worth every penny. The mechanic was super thorough and showed me exactly what was wrong. They fixed it while I waited, and the difference in how the car runs now is like night and day. No more whistling sounds, the acceleration is smooth again, and the engine light's gone. Fuel consumption has already dropped back to normal too. Can't believe my previous mechanic didn't check this first, could've saved me so much worry! Really grateful for your help in pointing me in the right direction. It's such a relief having it sorted properly without breaking the bank. Think I've found my new go-to mechanic too! Thanks again for sharing your experience, it made all the difference!