Mini Cabrio Engine Troubles

Oh dear, that sounds like a rather unpleasant situation! The symptoms you describe – check engine light, engine stalling, and reduced power – strongly suggest something amiss with the fuel system. When you say 'rail pressure sensor signal faulty,' what makes you think it's specifically that sensor? Have you had any diagnostic codes read? It's crucial to confirm the diagnosis before jumping to conclusions and replacing parts. Faulty wiring or connections can sometimes mimic a failing sensor, so examining those aspects would be prudent.

I see your point about the wiring. Where exactly should I be looking for potential wiring issues related to the fuel rail pressure sensor? Is there a specific connector or section of the harness that's known to cause problems on these Minis?

Okay, so the fault code points directly to the fuel rail pressure sensor. Given the symptoms you are experiencing, and with the fault code confirming your initial assessment, it is highly probable that the pressure sensor is indeed the source of your woes. While it's certainly possible to attempt a DIY fix, dealing with fuel systems can be tricky. I would recommend taking it to a trusted workshop. They'll be able to confirm the diagnosis and replace the sensor properly. It is preferable to let an expert do the work.

Just wanted to give an update. Took the Mini to a workshop, and they confirmed it was the fuel rail pressure sensor. They replaced it, and the engine is running smoothly again. The bill came to around 240€. Thanks for your help!