BMW X7 Temperature Mystery: Bad Sensor or Clogged Grille?

I experienced similar issues with my 2016 BMW X5 40i last month. The symptoms were identical, erratic temperature readings and slow warm-up times. Turned out the electric radiator grille flaps were stuck and a fuse was blown, causing the system to malfunction. The mechanic cleaned the grille assembly, replaced the fuse, and ran a full diagnostic check. They also found that these symptoms were causing the engine to run rich, which triggered the check engine light. It wasn't a major repair, but leaving it unfixed could've led to more serious engine problems down the line. Just make sure they check the fuse box and clean the entire cooling system properly. A proper BMW specialist should be able to diagnose this quickly with their diagnostic tools.

Thanks for sharing your experience, that's really helpful! I believe I'm dealing with the exact same problem. The symptoms match perfectly with what you described. Quick question, do you remember roughly how much you ended up paying for the repair? Also, has everything been running smoothly since the fix, or have you noticed any other issues pop up? Thanks again for your help with this!

Hey there! Happy to give you an update! Since my last post, everything has been running perfectly fine. The repair was actually pretty straightforward, they fixed the stuck cooling grille and replaced the faulty fuse which came to 52€. Money well spent if you ask me! The car's been performing great since then, no more crazy temperature readings, the engine warms up normally now, and the check engine light has stayed off. It's like having a completely different car! Trust me, getting it fixed was definitely the right call. These BMW engines are pretty sensitive to cooling issues, so it's always better to address these things early. Glad I could help you figure out what was going on with yours! I'd be interested to hear how your repair goes once you get it sorted. These X-series BMWs can be a bit finicky sometimes, but they're great cars when everything's running right.

Just wanted to update everyone, got my car fixed last week and wow, what a difference! Found a really good mechanic through a car enthusiast group. Took it in and they immediately spotted the issue, exactly what was mentioned about the grille and fuse. They cleaned everything up, replaced the necessary parts, and ran some tests. The whole thing cost me about €80, which was way less than I expected. The car's running like new now. No more weird temperature readings, engine warms up perfectly, and that annoying check engine light is finally gone! Actually feels better than when I took it to my previous mechanic who charged me three times as much and didn't fix anything. Thanks again for all the advice. It really helped me avoid getting ripped off again. Sometimes you just need to find the right mechanic who knows what they're doing!