GLA Diesel Fuel Pump Problems Engine Stalling

I have a GLA too, petrol version though, and engine stalling can be tricky. If the check engine light is on and you're experiencing rough running, a faulty fuel injector could be the culprit too. Have you checked for any error codes? If it's specifically pointing towards the fuel pump, it might be electrical. You mentioned a potential cable or plug issue. Is the fuel pump making any unusual noises before the engine stalls?

Error codes confirm fuel pump failure. No unusual noises, just the stalling and starting issues. I'm leaning towards the cable or plug theory as it seems intermittent. Is there a way to test the power supply to the fuel pump directly before replacing the whole unit? Is there any relation with fuel injector in this case?

Testing the power supply is a good idea. You'll need a multimeter to check the voltage at the fuel pump connector. Remember to consult the car mechanics' manual for the correct values. As for the fuel injector, it's less likely to be the direct cause if the error code is specifically for the fuel pump. They are separate components, but both affect fuel delivery. If the pump isn't providing enough fuel pressure, it can mimic fuel injector problems. Given your symptoms, my opinion is still a fuel pump issue, I would strongly suggest to have it checked by a workshop.

Thanks for the advice. Confirmed your suspicion it was indeed a corroded connector on the fuel pump. Cleaned it, reconnected, and the car runs perfectly. Total cost 95€ for diagnostics and cleaning. Happy it wasn't a complete fuel pump or fuel injector replacement!