Running With Out Gas

Not for long (I've heard a mile or so), and I understand that you risk damage to the hybrid system in that case.

It is important to note that the Prius is not an electric car, but rather a "regular" car that has an undersized engine which is supplemented by an electric motor. The hybrid system assumes that the engine is operational at all times.

- Doug

Outside the US the Prius has an EV switch which lets you run on electric only (you can retro-fit this switch on the US model too if you want to). You can't go very far on batteries though (maybe better on the next gen Prius with higher capacity batteries ?).

Paul

1. Can Prius run on electricity when it runs out of gas?

No. Though Prius can operate in electric-only mode when gasoline is in the tank, it is not designed to run without gasoline. Doing so could cause severe damage to the hybrid system, so drivers should be sure to keep gas in the tank at all times.

gasoline the dash lights up with many warning lights, like a christmas tree. (A code is stored in the computer, which can later be read by your mechanic...) The gasoline engine then is unable to restart, and you're on electric only. Depending on the speed you were going when you ran out of gas, and the terrain ahead of you, and the SOC (state of charge) of the hybrid battery when you ran out of gas, will depend on how far you can get on electric only. The usual comment is enough to get you to pull over at a safe place and call for roadside assistance, or maybe to the next service station. The farthest I've heard of someone going on electric only after OOG is about 2 miles - a UK NHW20 that was going about 65mph when OOG on a long downhill stretch.

I will note that you'll need at least 3 gallons of gasoline for the car to recognize that you've added some and restart.

If you try restarting the car too many times when OOG, then you'll deplete the hybrid battery (since the hybrid battery is used to start the gasoline engine). Rumor is that you'll need a special Toyota charger to get your hybrid battery in a working state again, and that there are few of these special chargers available (something like 2 for all of the US, maybe about the same number for UK/Europe). Thankfully, no one has been silly enough to run out of gas AND continuously restart their car without adding gasoline to get their Prius to this state...

While I haven't tried running out of gas with my Prius, a friend has -- twice. Both times it was while the car was on a highway. The battery provided enough power to move at low speed to a gas station. No subsequent damage was apparent and the car continues to work just fine.

TKM