BMW X3 Diesel: Glow Plug Problems Cause Cold Start Issues

Hey there! I've got some experience with BMWs and had a similar issue on my 2012 BMW X1 diesel last winter. I also own a 3 Series, so I'm fairly familiar with these cars. That preheating problem sounds very familiar. I had those exact symptoms, glow plug light staying on, rough cold starts, and even the same smoke during acceleration. The workshop found a damaged cable connection at the preheating control unit. The whole repair took about an hour and cost me 95 Euro, which included testing and fixing the connection. Before you get too worried, it might help if you could share: How many miles/kilometers are on your X3? When did these symptoms first appear? Have you scanned for error codes? Let me know these details and I might be able to help more specifically. The good news is, if it's the same issue I had, it's a relatively straightforward fix.

Had my X3 in for service just last week, sitting at 55200 KM. I was dealing with pretty much the exact same problem you described! In my case, it turned out to be more than just a loose connection, had to replace both the control unit and two glow plugs. The symptoms started showing up gradually, first just occasional rough starts, then got worse over a couple weeks. Used my buddy's diagnostic tool and pulled some error codes before taking it to the shop. Got P0380 and P0670 which pointed straight to the glow plug system. Might be worth checking those codes on yours too. The repair wasn't cheap, but the car runs like new now. Hope this helps point you in the right direction!

Hey again! Thanks for sharing your experience. Actually, my X1 also needed more than just the cable fix I mentioned earlier. After that initial repair, the problems came back after a few weeks, and I ended up having to replace the control unit and glow plugs too, just like you did. I pulled the same error codes, P0380 and P0670. My total repair bill came to around 800 for parts and labor, which wasn't fun, but honestly worth every penny. The car starts perfectly now, even in cold weather, and the smoke issues are completely gone. One thing I learned from this whole experience, if you've got these symptoms, it's best to get it fixed ASAP. I tried to cheap out initially with just the cable repair, but ended up potentially causing more stress on the engine. The mechanic mentioned that leaving it unfixed could have led to turbo problems down the line. Really glad you got yours sorted! These BMWs are fantastic cars when everything's working right. Now that we've both been through this, at least we know what to look out for in the future.

Thanks for sharing those details about your repair experience! It's actually really helpful to know I'm not the only one dealing with these glow plug system issues. The fact that both you and the other mechanic had similar experiences with your BMWs makes me feel more confident about getting this fixed properly. Your repair details are particularly useful since our cars had such similar symptoms. Think I'll go ahead and get the full repair done right away, control unit and glow plugs, rather than trying any halfway fixes that might need redoing later. No point risking any turbo problems like you mentioned! Getting those same error codes (P0380 and P0670) makes me pretty certain we're dealing with the same issue. While the repair cost isn't exactly cheap, it's better than letting it get worse. Really appreciate everyone's input on this. Time to book my X3 in for service and get this sorted once and for all!