206 petrol Stopping problem

My vehicle started to stop spontaneously in 206 1.4 gasoline vehicle, gave a p0463 fault, the fuel pump was changed with the float. But on the same day, it stopped again. I just noticed when it stopped, its temperature drops down and it doesn't work when it's down. I turned the ignition off and on a few times, and when the temperature gauge came back, the vehicle started. Has anyone encountered this problem, how should I proceed?

There may be a brain (ecu) malfunction. Touch the ecu with your hand when it is not working is there overheating? Or put a damp cloth on the ecu and wait for it to cool down a bit and start. Don't be afraid as the ecu is metal and waterproof

No warming up. It works occasionally, while everything is normal, it suddenly stops, sometimes it works, sometimes it doesn't.