I'm wondering about other people's experiences with the "check engine" light. I've had it happen a few times. I just had it happen during the past few days. I've found it is usually because the gas cap isn't seated properly or I got some inferior gas. I figured I would run the gas out and then put some better gas in. But the light went off with still a third of a tank of gas. I don't know what caused it to come on or what caused it to go off. I think a lot of Volt owners freak out needlessly over the check engine light. The owner's manual suggests you drive for a while and see if the light goes out. It has always gone away after a few days. If the check engine light is flashing you do have a problem and you shouldn't drive your Volt. That has never happened to me.