BMW 5 Hybrid Power Loss & Failed Emissions Mystery

Hey there! I had very similar issues with my 2020 BMW 3 Series Hybrid last winter. Started with the check engine light and reduced power, just like yours. The exhaust leak was causing incorrect readings in the emissions system, which triggered the power reduction mode, it's a safety feature in these cars. After a thorough inspection, turned out the exhaust manifold had developed a crack, which was affecting the NOx catalyst system. It was pretty serious since it could've damaged other components if left unchecked. The repair involved replacing the manifold and the catalyst assembly. It was a few days' job but worth fixing properly. My suggestion would be to get a proper diagnostic scan first. These hybrid systems are complex, and the symptoms you're describing match exactly what I experienced. Make sure whoever looks at it has specific experience with BMW hybrid systems, they're quite different from regular models. Good luck with the repair.

Thanks for sharing your experience, sounds exactly like what I'm dealing with! This is super helpful. Can I ask how much the manifold and catalyst replacement ended up costing you? Also wondering if you've had any other issues pop up since getting it fixed? Really trying to figure out what I'm in for here, both repair-wise and budget-wise.

Hey again! Happy to give you an update! After getting it properly fixed, I haven't had a single problem, it's running like a dream. The whole NOx storage catalyst aging issue was sorted out completely, and the exhaust leak repair was surprisingly reasonable at 265€. Way less than I initially feared! The best part is that the power is fully back to normal, and I'm passing emissions tests with flying colors now. Trust me, getting it fixed properly was totally worth it. My BMW's performing exactly like it should, and I haven't seen that pesky check engine light since. Just make sure you find a mechanic who really knows these hybrid systems, that's what made the difference in my case. They spotted the issue right away and fixed it properly the first time. Honestly, it's such a relief to have it sorted, and the car feels better than ever. Hope this helps give you a better idea of what you might be looking at. Let me know if you need any other info!

Thanks so much for all the details! You've made me feel way better about this whole situation. I actually just got back from a mechanic who specializes in hybrids, and guess what? You were spot on! Had pretty much the same issue you described. Got the work done this morning, they replaced the catalyst and fixed a small exhaust leak. The whole thing took about six hours, but wow, what a difference! The car's running smooth again, no more power loss, and that annoying check engine light is finally gone. The price was pretty close to what you paid too, which was a huge relief. Was definitely worth getting it sorted by someone who knows these systems well. They even showed me what was wrong and explained everything clearly, such a different experience from my last mechanic visit. Really appreciate you sharing your experience, helped me make the right decision instead of putting it off and potentially causing more damage. Thanks again!