is you head off a 6.9?hot air junkie?in my opinion unless your living in the arctic you dont need a fuel heater.i just deleted mine and put an inline filter on to be honest.the instructions actually came from plc7.3 so i cant take full credit.i originally did the inline filter until i got time to redo the o-rings and i still havent got around to it and that was a year ago.lol