Recently began driver training on this vehicle with my son (at approximate vehicle mileage of 8,500). Vehicle is manual transmission and had never previously been stalled. Once vehicle had been stalled during driver training, reduced vehicle power was available, creating an unsafe condition when attempting to merge into traffic or driving on an uphill grade. The issue produced no warning message or CEL but did produce a pending OBDII error code of P2615 (camshaft signal output circuit low). The error appears to resolve after a full restart (shut down, unlock and open door, close door, restart). The error is reproducible and has occurred on multiple occasions. The error does not reset if simply restarting vehicle without opening door between restart. I have scheduled an appointment for evaluation by dealer, but it has not yet been confirmed by dealer. I believe this is a manufacturing defect, as the same issue occurs on another identical car owned by me.