Have you tried starting this engine at all,if not then check your fuel is selected on,on the control stand,and fuel pump on the o/h panel,and press the eng 2 start button on the o/h panel,keep it pressed untill the red light above start push comes on,then release start push,to get gen on once eng running,select gen switch to full left then to on,i dont know why your aircraft is not getting all 4 engs running when aircraft is selected,i know that you can get the aircraft selected into fs9 with either all 4 engs running,or all 4 engs off,i.e. cold dark set up.
regards alan.