Peugeot 408 hybrid engine stalling

Sounds like a potential fuel pressure issue. When the engine stalls, does it happen more often when the fuel tank is low? Also, have you scanned the car for error codes? That would give you a better idea if the rail pressure sensor is indeed the problem. Sometimes, a clogged fuel filter can cause similar symptoms by starving the engine of fuel, and a failing fuel pump can also cause the same symptoms.

Thanks for the tips! No, the fuel level doesn't seem to make a difference, and yes I did scan it - it threw a code indicating a problem with the rail pressure sensor signal. A clogged fuel filter isn't out of the question, but I wanted to start with the sensor first. Where exactly is the fuel filter located in the 408 hybrid?

Okay, the error code makes it pretty clear. While it could be a wiring fault, if the code specifically mentions the sensor signal being faulty, it probably is a defective sensor. To be honest, I'm not 100% sure where the fuel filter is located on your specific model, and it can sometimes be integrated with the fuel pump, inside the fuel tank. Given the symptoms and the error code, I'd recommend taking it to a trusted mechanic for diagnosis and repair. Replacing the sensor yourself might not solve the problem if there is something else at play.

You're right, I think I'll take it in. Turns out it was indeed a faulty rail pressure sensor. The shop replaced it for 240€ and now it runs like new again. Thanks for the help!