BMW 6 Diesel Losing Power? DISA Valve Could Be Culprit

Hi there! I've got some experience working on BMWs. I had a similar issue with my 2020 BMW 5 series diesel last year. The symptoms were exactly like yours, poor performance, rough idle, and that annoying check engine light. My owns a 3 series and recommended checking the DISA valve. Took it to my trusted workshop and they confirmed it, the DISA unit was completely shot. The repair cost me about 280 Euro, and it fixed all those issues. The car's been running smoothly since then. Could you share which engine variant you've got? Also, are you getting any specific error codes? This would help me give you more targeted advice. Different engine types can show similar symptoms but might need different approaches.

Hey, thanks for sharing your experience! Mine's actually at 142617 KM and just had its service last month. After reading your response, I'm even more convinced it's the DISA valve. The symptoms match perfectly, especially that rough idle you mentioned. I've got the diesel straight-six and I'm getting the P1017 error code. Really appreciate your input on the repair costs too, good to know what I might be looking at. Guess I'll have to bite the bullet and take it to the shop. Would you recommend getting it sorted ASAP, or is it okay to drive it for another week or so? Just hoping it won't turn into something bigger if I wait a bit. After all, these BMWs can be pretty expensive to fix when things go wrong!

Hey! Small world, I actually fixed my DISA valve issue just about a month ago, so I can definitely help with your question about timing. Look, I totally get wanting to put it off, nobody likes unexpected repair bills! But from my experience, I wouldn't wait too long. When my DISA valve started acting up, I tried driving it for about two weeks, and honestly, it just got worse. The rough idling became more frequent, and the power loss was really noticeable, especially when merging onto highways. With that P1017 code (got the same one myself), it's definitely the DISA valve. Here's the thing, continuing to drive with a faulty DISA valve can potentially cause more problems with the engine management system. In my case, I noticed my fuel consumption went up quite a bit while trying to squeeze in a few more days before the repair. My advice? Get it sorted within the week if you can. The repair itself isn't too complicated, took them about 2-3 hours for mine. Better to fix it now than risk more expensive issues down the line. These straight-six engines are generally solid, but they do need proper maintenance when something's off. Let me know how it goes when you get it fixed! Always interested to hear how these repairs turn out for others.

Thanks so much for that detailed advice! You've definitely convinced me to get it looked at sooner rather than later. I've actually just called my mechanic and booked it in for this Thursday, better safe than sorry, right? Really good point about the fuel consumption too, now that you mention it, I have been noticing I'm filling up more frequently lately. Didn't make the connection until you pointed it out. The last thing I want is to cause more damage by being cheap about repairs now. It's actually quite reassuring to hear that the repair was straightforward for you. I was worried it might turn into one of those "while we're in there" jobs where they find ten other things that need fixing! Really appreciate you taking the time to share your experience, it's helped me make up my mind. I'll probably post an update once it's all sorted, in case anyone else runs into the same issue in the future. Thanks again!