BMW i3 Hybrid Stalling: Tank Vent Valve Issues?

Hey! I've got some experience working with hybrids. I ran into something similar with my 2015 BMW i8. Actually, my mechanic discovered it was clogged hoses rather than the ventilation valve. The symptoms were exactly like yours, emergency mode, check engine light, and stalling issues. Took it to my regular workshop and they did a thorough cleaning of the hoses, cost me around 175 Euro but solved the problem completely. Haven't had any issues since then. Before I can share more specific details, what's your mileage and have you noticed any other symptoms? Also, have you had any recent work done on the car? This could help identify if we're dealing with the same issue. The i3 and i8 share quite a few components in their hybrid systems, so I might be able to point you in the right direction with more info.

Thanks for the detailed response! My i3 just hit 185480 KM and had its latest service about 4 months ago. The stalling started happening last week, and I've also noticed a slight hesitation when accelerating from a stop. No other work was done recently except for regular maintenance. I'm hoping it's just clogged hoses like in your case, that sounds better than having to replace the whole ventilation valve assembly. Did your mechanic mention how common this issue is with BMW hybrids?

Hey again! Really glad I can help out here. Yeah, after reading about your mileage and symptoms, it sounds even more similar to what I experienced with my i8. That hesitation during acceleration was exactly what I had too, should've mentioned that in my first reply! My mechanic actually told me it's pretty common in BMW hybrids, especially once they get past 150,000 KM. The hoses tend to accumulate gunk over time, and the hybrid system is particularly sensitive to these blockages. In my case, they first suspected the ventilation valve too, but after inspection, they found that cleaning the hoses fixed both the stalling and that annoying hesitation during acceleration. The whole job took about 3 hours. Quick tip though, make sure your mechanic checks the connections around the purge valve while they're at it. When they were cleaning my hoses, they noticed one of the connections was a bit loose, which probably contributed to the problem. If you want, I can share my mechanic's full diagnosis report with you, might help when you take it in. Just let me know!

Thanks so much for all this information, it's super helpful! That's really interesting about the loose connection near the purge valve too. I'd actually love to see that diagnosis report if you don't mind sharing it. I'm feeling much more optimistic now knowing it might just be a cleaning job rather than a major repair. I'll make sure to mention these specific points about the hoses and connections when I take it to the workshop tomorrow. It makes total sense given my car's mileage, and honestly, I'm relieved to hear it's a common issue. Was starting to worry I'd need to shell out for something much more expensive! I'll let you know how it goes after the workshop checks it out. Really appreciate you taking the time to share your experience, it's definitely helped me understand what I might be dealing with here!