BMW M2 Cold Start Issues, PTC Heater Problems?

Hi there! I have some experience working on cars and had a similar issue with my 2021 M4. I feel your pain with those cold start problems! When mine acted up with almost identical symptoms, it turned out to be a faulty electric auxiliary heater. The repair shop ran diagnostics and confirmed it was causing the excessive fuel consumption and warming issues. Ended up costing me around 350 Euro to get it fixed, but it was worth it, car runs perfectly now. Can you share more details about when you first noticed these issues? Also, are you getting any specific error codes with that check engine light? That would help narrow things down and see if it's the same problem I had. By the way, if it is the PTC heater, don't wait too long to get it checked. Mine got worse pretty quickly and started affecting overall engine performance.

Thanks for sharing your experience! Mine's at 96823 KM and just had its service last month. The issues started about 2 weeks ago, right after a particularly cold morning. Getting error code P0597 which points to the thermostat heater circuit. Really helpful to know about your M4 repair costs, gives me a ballpark figure of what to expect. Guess I'll bite the bullet and get it checked out this week before it gets worse. The fuel consumption is really starting to bug me, and these cold starts are getting more annoying by the day.

Hey again! Thanks for the update on your M2. Yeah, that P0597 code definitely rings a bell, it's exactly what I saw on my M4 before getting it fixed. Looking at your mileage and the timing of when it started, it's pretty much identical to what I experienced. When my issues began, I also noticed it right after a cold snap, and the fuel consumption just kept getting worse. I actually tracked it, was using about 15% more fuel than usual before I got it sorted. Those cold morning starts were brutal, right? Mine would shake like it was running on 3 cylinders! Since you mentioned getting it serviced last month, I'd check if this might still be under warranty. My repair would've been pricier, but I caught a break with some warranty coverage. The thermostat heater circuit repair ended up being pretty straightforward once they got to it. Pro tip from my experience, while they're in there, have them check the surrounding wiring too. My mechanic found some slightly corroded connections that could've caused problems down the line. Let me know how it goes when you get it checked out. I'm curious if your repair bill ends up being similar to what I paid. These M-series cars can be finicky with their heating systems, but they're worth the hassle!

Thanks so much for all the detailed info! I just checked my warranty status, still got 3 months left on it, so that's a huge relief! Really appreciate the tip about checking the wiring too, I'll definitely mention that to the mechanic. It's super helpful knowing someone else went through the exact same thing, especially with that P0597 code. You've saved me a lot of worry about whether this is a major issue or not. I've booked it in for tomorrow morning, and I'll keep an eye on those connections you mentioned. Totally agree about these M cars being worth the hassle, even with these issues, I still love driving it! I'll probably update the thread once I get the diagnosis, might help someone else down the line with the same problem. Thanks again for all your help!