An energy module determines an amount of energy consumed by an electric heater of a fuel vapor canister since an ignition system of the vehicle was last transitioned from OFF to ON. A purge valve control module controls opening a purge valve while the ignition system of the vehicle is ON, wherein fuel vapor flows from the vapor canister through the purge valve to an air intake system when the purge valve is open. A heater control module selectively applies power to the electric heater of the fuel vapor canister and, based on at least one of the amount of energy consumed by the electric heater and a mass of fuel vapor that has flowed through the purge valve, selectively disconnects the electric heater from the power until after the ignition system is transitioned from ON to OFF.