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SpeedyGerd

BMW 2 Series Diesel Power Loss & Rough Idle Mystery

Loss of engine power

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Check engine light on

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Stalling while idling

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Fault stored

Hi all! Having some trouble with my 2021 BMW 2 Series diesel (12,088 KM). Engine's been acting up lately, power feels weak, check engine light is on, and it's running rough at idle. Sometimes it even stalls. I suspect it might be the DISA valve. Had a not-so-great experience with my last mechanic, so I'm looking for advice. Has anyone dealt with similar symptoms? Were they DISA valve related? Would love to hear about your repair experiences and maybe get some trustworthy mechanic recommendations. Thanks in advance!

4 comment(s)


GNeumann91

Hey there! I had almost identical issues with my 2018 BMW 4 Series diesel last summer. The symptoms matched yours exactly, sluggish power, rough idle, and that annoying check engine light. Got it checked at my garage and yeah, it was the DISA valve. Had to replace the complete DISA unit because the changeover valve was shot. It's a critical component that controls air flow into the engine, so you definitely don't want to ignore it. My repair took about 4 hours, they had to remove quite a few parts to access it properly. While it wasn't cheap, it was worth fixing right away because these issues can lead to bigger engine problems if left unchecked. Since getting it fixed, the car runs like new again, smooth idle, proper power delivery, and no warning lights. I'd suggest getting it looked at soon since your symptoms are so similar to what I experienced. Best of luck with the repair.

SpeedyGerd (Author)

Hey, thanks for sharing your experience! Sounds exactly like what I'm dealing with. Quick question, do you remember roughly how much you ended up paying for the DISA valve repair? Also, has everything been running smoothly since then, or have you noticed any other issues pop up? Just want to know what I might be in for both cost-wise and if I should expect any related problems down the line. Thanks!

GNeumann91

Hey again! Yeah, I can tell you exactly what I paid, it was 280 € for the complete DISA unit replacement. Pretty straightforward job for my mechanic, really. And honestly it was money well spent because the car's been running absolutely perfect since then, no more rough idle, no more power issues, nothing! It's been about 8 months now since I got it fixed, and I haven't had a single problem with anything related to that system. The engine runs smooth as butter, just like when I first got the car. No warning lights, no weird noises, nothing to worry about at all. If your symptoms are matching what I had, I'd say just go for it and get it sorted. The longer you wait, the more strain you're putting on other engine components. Trust me, getting it fixed properly the first time around saves you headaches later on. Just make sure you get a genuine BMW part, that's what I did, and I reckon that's why I haven't had any issues since. Hope this helps!

SpeedyGerd (Author)

Thanks so much for all the details! I actually just got back from the mechanic today, you were spot on about everything. Had the same repair done and thankfully caught it early. My wallet's a bit lighter now, but the car's running like a dream again! The mechanic was great, really took the time to explain everything and show me the old DISA valve. Pretty wild how such a small part can cause so much trouble! They did the whole job in about 3 hours, and the cost was pretty much in line with what you mentioned. Took it for a proper test drive after, and what a difference! No more rough idle, power's back to normal, and that annoying check engine light is finally off. Feels like I've got a new car again. Really appreciate you sharing your experience, helped me feel a lot more confident about getting it sorted. Here's hoping mine stays trouble-free like yours has!

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