Originally Posted by myrt1987
I mostly notice it with 1/4 tank or less it takes more gas to maintain the same speed. I cant explain it myself.
Just a wild guess but maybe it could have something to do with the smaller amount of gas and the EVAP system / charcoal vapor canister. The system was designed to reduce pollution and draw fuel vapor into the engine to increase fuel efficiency. As the fuel level decease, the concentration of vapors decrease and the mpg's decrease. Feels like I'm grasping at straws, lol.