How can you use the evaporative recovery system to improve milage?

Question

suck the fumes from the tank

Answer 1

you evaporative emissions system does not improve mileage, it just reduces emissions.  specifically carbon emissions.  hydro-carbons escape in the form of evaporated gasoline.  the gasses are recovered by the evap system and are burnt through the engine at cruising speeds.

Answer 2

My friend, forget it. This system will throw off your entire computer, and all the emissions, and the car will constantly run lean!!!!