GE Water heater

Paul S_3

hey everyone....i went on a "no hot water call" on a GE water heater fairly new 2007 and found when i lit the pilot and switch the gas control valve knob to ON ....it looked as if the flame was getting sucked down....i seen a metal rod that was sticking up right under where the main burner would sit.....if i keep this rod down it runs but with it up it doesnt....never seen it before...i dont want to change this heater if it can be fixxed....thanks

PAUL S