BMW i3 Cold Start Issues: Fix Your Rough Morning Engine

Hey there! I've got some experience working on cars (not a pro, but I've dealt with my share of issues). Had a similar problem with my 2014 BMW i8 last winter, sounds exactly like what you're describing. The symptoms matched perfectly: rough starts, multiple cranking attempts, and higher fuel consumption. My local workshop confirmed it was indeed a faulty injector valve. The repair set me back about 515 Euro, but it solved the issue completely. They had to replace the defective injector and recalibrate the system. Before we dive deeper, could you share: How many miles/kilometers on your i3? Are you getting any specific error codes? Do you hear any unusual clicking sounds when trying to start? This would help me understand if you're dealing with the exact same problem I had. BMW hybrids can be tricky, but once you get the injection system sorted, they run like clockwork!

Thanks for sharing your experience with the i8! My i3 just hit 110960 KM and had its last service about 2 months ago. Actually, I do hear a clicking sound when starting up, it's quite noticeable in the mornings. No error codes showing up on the dashboard though, which makes it a bit trickier to diagnose. That repair cost doesn't sound too bad if it fixes the issue completely. Did you notice any early warning signs before your injector completely went bad? Just trying to figure out if I should get this sorted ASAP or if I have some time to plan for the repair.

Hey again! Glad to help out with more info about my experience. Yeah, looking back, there were definitely some warning signs with my i8 before the injector completely gave up. The clicking sound you're describing is exactly what I experienced, it started off subtle but got more noticeable over time, especially during cold mornings. In my case, I noticed the fuel consumption gradually creeping up over about 2-3 weeks before things got really bad. Started with maybe a 10% increase, then kept getting worse. The rough starts also followed a similar pattern, first just a slight hesitation, then progressed to the multiple start attempts. With your mileage being pretty close to what mine was (mine had about 108000 KM when this happened), I'd honestly recommend getting it checked sooner rather than later. The reason I say this is because I waited too long, and it ended up causing some carbon buildup in the intake system. Had to get that cleaned out too, which added to the cost. One thing I learned, these injection systems are pretty sensitive in hybrids, and problems tend to snowball if left unchecked. The fact that you're not getting error codes yet is actually pretty typical, mine didn't show any codes until things got really bad. Trust me, better to deal with it now while it's just the injector. The repair itself only took about half a day at the workshop, and the car's been running perfectly since then. If you need any specific workshop tips, just let me know!

Thanks a lot for the detailed breakdown! That's really helpful to know about the progression of symptoms you experienced. You've convinced me, I'm definitely going to book it in for a check next week. Don't want to risk any additional carbon buildup issues like you mentioned. It's reassuring to hear the actual repair was pretty quick once they got to it. Since my symptoms are so similar to what you experienced, and our cars had comparable mileage when the issues started, it seems like this is probably the same problem. Really appreciate you taking the time to share your experience, it's helped me stop second-guessing whether this needs immediate attention or not. I'll update the thread once I get it sorted out. Thanks again for all the advice!