BMW Z4 Stalling & Power Loss: DISA Valve Warning Signs

Hey there! I had nearly identical issues with my 2017 BMW M240i last year. The symptoms matched yours exactly, rough idle, stalling, weak power, and the dreaded check engine light. My diagnostic showed it was indeed a faulty DISA valve. Had to replace the complete DISA unit. It wasn't a quick fix, my car stayed at the garage for two days because they needed to access the intake manifold to get to the DISA valve. You definitely don't want to ignore this, a failing DISA valve can lead to more serious engine problems if left unchecked. After replacement, the difference was like night and day. Engine ran smooth again, power was back to normal, and no more stalling issues. My advice would be to get it checked soon, these symptoms are pretty typical of DISA valve failure on these engines. Look for a shop that specializes in BMW repairs, it's not something you want a general mechanic messing with. Best of luck!

Hey, thanks a lot for sharing your experience! It's really helpful to hear from someone who had the same problem. I'm relieved to know it was just the DISA valve and not something more serious. By the way, do you remember roughly how much you paid for the repair? Also, has everything been running smoothly since the replacement, or have you noticed any other issues pop up?

Hey again! Glad to give you an update! I spent 280 € on the complete DISA unit replacement, which honestly wasn't as bad as I feared it might be. And I've got great news, since getting it fixed, my M240i has been running like a dream. It's been about a year now, and I haven't had a single issue related to the DISA valve or anything similar. The power delivery is spot-on, idle is butter smooth, and that annoying check engine light is long gone. It's actually amazing how much difference a properly functioning DISA valve makes, my car feels just like when I first got it. The mechanics did a solid job, and I'm really happy I didn't wait any longer to get it sorted. Trust me, you won't regret getting it fixed. Just make sure you go to someone who knows their way around BMWs. Hope this helps with your decision making!

Thanks so much for all the details! You've really helped me make up my mind. I actually just got back from a BMW specialist mechanic today. You were spot on, it was the DISA valve causing all the trouble. The repair cost was a bit higher than yours at 350 €, but honestly, it was worth every penny. The whole process took about three days because they were pretty busy, but the results are amazing. The car feels completely transformed, smooth idle, strong power delivery, and no more check engine light. The mechanic I found was great too, really took the time to explain everything and even showed me the old DISA valve to point out what had failed. I'm just glad I asked here first and got your advice about going to a BMW specialist. You saved me from potentially making another bad mechanic choice. The car's running perfectly now, and I couldn't be happier with how everything turned out. Thanks again for helping me make the right decision!