The only 3 amp fuse I recall on my 84 Firebird is for the dashlights. The spot that says crank/3 has no pins for plugging a fuse in. My next quess is the choke cover/heater on the side of the carb.. Disconnect that. Were you tinkering with anything, and if everything is working, what lead you to check it. Looking for the missing link, with the above questions. HTH Bruce