[TXSchnee]

I run a PHEV now, would never do so with zero gas, they are not designed to operate as a BEV. It should be fine with a 1/4 tank, but never run on empty. Per Toyota, but applicable to all PHEV systems: "Though a hybrid vehicle 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."