BMW X4 Fuel Rail Issues: Stalling and Power Loss Help

Hey there! I had a pretty similar issue with my 2013 BMW X3 last year (I have some experience working on cars, but nothing too crazy). Those symptoms sound exactly like what I dealt with, the car was a mess with rough idles and kept dying on me. My local workshop confirmed it was indeed a faulty pressure sensor. I first tried cleaning the sensor myself but that didn't help at all. Finally took it to my trusted mechanic who diagnosed and replaced the rail pressure sensor. Total bill came to about 240 Euro, including labor. The car's been running perfectly since then. Before I can share more specific details, could you tell me your engine size and mileage? This might help pinpoint if we're dealing with the exact same issue, as different engine variants can have slightly different setups. Also, have you scanned for any specific error codes? And just curious, did these symptoms appear gradually or was it more of a sudden thing?

Thanks for the detailed response! My X4 has a gasoline engine and I've only done 19954 KM since I got it. Had the latest service done just recently. The symptoms started gradually over the past couple weeks, getting worse by the day. Haven't pulled the codes yet but planning to do that tomorrow. Your experience with the pressure sensor sounds spot on, same symptoms I'm dealing with. That repair cost doesn't sound too bad either, I was worried it might be something more serious. Did you notice any warning signs before it started acting up? Really appreciate the help!

Hey again! Yeah, looking back at my X3's issues, there were definitely some warning signs I probably should've caught earlier. About a month before things got really bad, I noticed the engine would occasionally hesitate when accelerating from a stop, kind of like a slight problem. I brushed it off thinking it was just bad fuel or something. The idle problems started off pretty subtle too, just a tiny wobble here and there that I barely noticed. But it got worse pretty quick after that. Within about two weeks, it went from that small wobble to full-on stalling. Sounds exactly like what you're experiencing with your X4. Since you mentioned your recent service, double-check if they replaced the fuel filter. Sometimes a clogged filter can mimic pressure sensor symptoms. In my case, I actually wasted time replacing the fuel filter first before figuring out it was definitely the sensor. One tip, when they replace the sensor, make sure they check the wiring harness too. Mine had a bit of corrosion on the connector that needed cleaning. Could've caused problems again if they hadn't caught it. Keep us posted on those codes when you get them! If they're anything like what I got, it'll probably confirm the pressure sensor theory. The repair really isn't too painful on the wallet, and it's definitely worth fixing before it leaves you stranded somewhere.

Really appreciate all this info! Those warning signs you mentioned, the hesitation from a stop and subtle idle wobble, that's exactly what I experienced in the beginning too. I also ignored them thinking it was just bad gas or something minor. Won't make that mistake again! Good point about the fuel filter, I'll check my service records tonight to see if they replaced it. And thanks for the tip about the wiring harness, I'll definitely mention that to my mechanic. Better to catch any potential issues while they're in there anyway. I'll get those codes pulled tomorrow and update the thread with what I find. Feeling much better about this whole situation now. Was really stressing about potentially major engine problems, but this seems way more manageable. Thanks again for sharing your experience, super helpful!