Methanol-gasoline blends have attracted a great deal of attention as automotive fuels for both environmental and economic reasons. To better understand the effect of methanol concentration on activated carbon performance, cycling tests with new carbons and several different methanol:gasoline ratios were undertaken. The data obtained indicate that the keys to activated carbon performance with methanol-blended fuels are the pore size/volume characteristics. It was determined that the working capacity to breakthrough for methanol blends of 0, 10, and 35% by volume were similar but that the working capacity for 85% methanol was significantly lower. When the same carbon was cycled sequentially with gasoline and different concentrations of methanol, the adsorption/desorption performance tended to adjust or recover to levels expected.