I know that when the EV gage reaches 2 bars it means that there is no EV left. Is this the case for the fuel gage? I prefer not to trust the HV estimate but to go based on the remaining bars on the fuel gage and/or the warning light that comes on. Also, if the warning light comes on my understanding is that one can still drive at least 33 miles before running out. Is it bad for the engine to let it run that low? Should I make it a point of filling up at 1 or 2 bars instead? Or simply to wait for the light?