Yesterday, after installing my LCA bushings I was on my way to get gas. I was pushing my mileage because I hadn’t checked it in awhile and Sunoco offers 93 for the price of 89 on Fridays. Anyway right after I get the car back together and start it my battery light starts to flicker. It gets so its staying on. After I go past 2200rpm it goes off. Anytime I drop back below 2200 it comes back on. Im thinking great, one problem solved another arises. To my amazement after I fill the tank I never see the light again. WTF caused this??? BTW i went 369 miles, took 11.17 gallons to fill @$1.38/gal of 93 octane, which is 33 MPG.
My battery light started flickering too but it was because the cable connector on the positive end (red) was loosened and could have easily disconnected and killed all the power in my car. Thankfully I noticed it was loose and tightened it again – not sure if this is your problem but you might want to check the actual battery as well as what it has to do with fuel.
Go have your alt. and battery tested. When they test it, most likely a problem wont show because the system will be charging correctly hence the light being off. My car did it off and on for few weeks so i hooked up a DMM to a hot lead in the car. Sure enought everytime the batt. light came on the voltage would drop from a steady 13.8-14.0 to around 11.0-11.5 volts. I changed out the alt. and everything was fine afterwards. Ohh and the first time the light came on was after i did a header install pulling out of my driveway.
Same thing happened to me
Everythings fine now that i filled up with gas.
Originally posted by Slacker
Everythings fine now that i filled up with gas.
BOOYAH
i don’t know why its only when your empty but i had a similar prob. when my belt was loose. its always the simple things.
Originally posted by Slacker
Everythings fine now that i filled up with gas.
Well, then all you have to do is never run low on gas. 
Actually, I bet money on the alternator, like Beatu said. I had the flickering battery light problem and it was the alternator. Had it rebuilt. Runs fine now. Good luck.