BMW M4 Oil Sensor Triggers Limp Mode, Help Needed

Had a similar issue on my 2012 BMW M3 last month. The limp mode and check engine combo is nerve-wracking, but in my case, it was just a faulty connection to the sensor rather than the sensor itself. The wiring harness had some wear and caused intermittent signals. The mechanic showed me that the connector pins were slightly corroded and the protective sleeve was damaged. They cleaned the connections, replaced the wiring sleeve, and secured it properly. No issues since then. Not a serious fix, but leaving it unfixed could lead to bigger problems. If you're getting oil temp sensor codes, have them check the wiring and connections first before replacing the whole sensor unit. Save yourself some headache. These sensors are pretty reliable usually, so it's often the connections causing trouble.

Thanks for sharing your experience! Really useful info about checking the wiring first. Could you tell me roughly what you paid for the repair? Also, just curious, has everything been running smoothly since the fix, or have you noticed anything else acting up? I'm trying to get an idea of what I might be looking at cost-wise and whether I should expect any related issues down the line with my M4.

Hey there! Just wanted to follow up on your questions. The repair turned out great, it was definitely worth getting it sorted quickly. The mechanic found exactly what I suspected, a faulty engine oil temperature sensor caused by dodgy cable connections. Total bill came to 95 € for fixing the wiring and connections, which was a relief since I was worried it might be something more serious. Since getting it fixed, my M3's been running like a dream. No more limp mode, no warning lights, nothing. It's been about six weeks now and everything's working exactly as it should. You really don't need to worry about related issues popping up, once the connection is properly fixed and sealed, it's sorted. Actually, my mechanic mentioned these connection issues are pretty common on our BMWs. The good news is that if you catch it early like I did, it's usually a straightforward fix. Your M4 should be back to normal once they sort out those connections. Let me know how you get on with yours!

Just wanted to update everyone, took your advice and got it sorted! Brought it to a new mechanic who actually took the time to explain everything. You were spot on, it was mainly a wiring issue. The connections had gotten loose and corroded, causing those weird temp readings. The repair was surprisingly reasonable, around 120 bucks for cleaning, rewiring, and weatherproofing the connections. Way better than the 500+ my old mechanic wanted to charge for replacing the entire sensor unit! The best part? Car's running perfectly now, no more limp mode or check engine lights. Really glad I asked here before jumping into expensive repairs. Amazing how something as simple as bad wiring can cause such a headache. Thanks again for sharing your experience, saved me both time and money!