Awww, Lioness, have you ever had your chart done? You could have your fire sign Sun & Moon in aspects or houses which put a damper on outward expression. For instance, my Pisces Mars (pretty terrible placement for Mars to begin with), is totally unaspected to anything else in my chart. This does not translate well for being a person with drive, ambition, or persistance. Despite being seriously outgoing, I have no sales talent whatsoever. I couldn't sell the cure for AIDS.
If its a planetary aspect or house placement problem, once again, having your chart done would help. Your fire sign planets can be energized through transits, progressed planets energized through transits and energizing your natal planets. Having this done will let you know when these times will occur, so you can plan to make use of your fiery qualities ; )