Stall at idle

The code B2078 is actually P2078. "P" meaning Power Train (engine) malfunction. This code means the intake manifold mixture/blend valve is malfunctioning/stuck. Since it does not activate below 2600 rpms and you are have trouble below that speed, while idling, I would guess it is stuck open and messing up the fuel/air mixture. There are some sensors that may send a false signal too. A good mechanic would first try to locate that moving part that's not moving, and free it up. You can Google that code for a more complete answer. It's not serious....just annoying.

Air filter maybe clogged. Change it

Thank you everyone. Update: Nissan report said loose wire. “Secured ground wire to engine and test drove, good after” So far so good.