Carnot start car not start cod P1391

This is an intermittent error caused by the lack of signal occasionally from either the cam or the crank sensor. I would remove and clean both. Check the wiring connections both to the sensors and back to the ECU. Sometimes a bit of dirt or corrosion can interrupt things a little bit so a good clean and brush up usually does the trick. Unplugging and plugging connectors a few times helps make fresh connection. If in doubt replace both.