BMW 2 Series Intake Manifold Problems, Power Loss Help

Hey there! I have some experience with BMWs and had a similar issue with my 2012 BMW 1 Series diesel. The symptoms you're describing sound exactly like what I went through last year. Had the same problems, rough running, power loss, and that annoying hissing. Took it to my regular workshop and they diagnosed a faulty intake manifold control switch. The repair set me back about 465 Euro, but it completely solved the issue. The car's been running smoothly since then. Just so I can help more specifically, what's your exact engine size and mileage? Also, does your check engine light come on? These details would help confirm if it's the same issue I had. If it turns out to be the same problem, I'd recommend getting it fixed soon. Driving with a faulty intake manifold can lead to bigger issues down the line.

Thanks for sharing your experience! My car has 57390 KM on the clock and had its last service 3 months ago. I'm actually getting those exact same symptoms, the hissing noise and power loss are really bothering me. The check engine light has been flickering on and off, especially during cold starts. Really good to know about the repair cost, gives me a better idea of what to expect. Guess I better get it checked out soon before it causes any bigger problems.

Hey again! Glad to help further. Looking at your mileage and symptoms, it's definitely similar to what I experienced. My BMW was around 62000 KM when I had the same issue. That flickering check engine light during cold starts is a dead giveaway, exactly what mine did before I got it fixed. The cold start symptoms tend to get worse over time if left unchecked. After I got mine fixed, the difference was like night and day. The engine became super smooth, and that annoying hissing completely disappeared. Quick tip from my experience, when you take it in, ask them to check the electrical connectors to the manifold too. In my case, they found some corrosion on the connectors that needed cleaning. This was included in the repair cost I mentioned earlier, but it's worth mentioning to make sure they take a look. Also, since you mentioned your last service was 3 months ago, did they say anything about the intake system during the service? Sometimes these issues start small and gradually get worse. Let me know how it goes when you get it checked out, always interested to hear if others have the same fix work for them.

Thanks for the detailed advice! No, they didn't mention anything about the intake system during my last service, but to be honest, these symptoms really started showing up about a month ago. Really appreciate the tip about checking the electrical connectors, I'll definitely mention that when I take it in. I've actually already booked it in for next week at my regular mechanic. The price you mentioned seems reasonable, especially if it includes the connector cleaning too. I'd rather get it sorted now than risk more expensive repairs later. Will let you know how it turns out and if it's the same fix that worked for you. Thanks again for all your help!