Hi everyone, I have a 2012 Prius ( Model 4). I have been using 87 octane, unleaded, ehtanol added gasoline. Is it safe and to used 91 octane, unleaded, ethanol-free gasoline? Would it be better for the vehicle? thanks
If that's your only option to try ethanol free, sure I'd try it. It won't damage anything. Up here the only ethanol free option I've seen is chevron's TOP octane. Never tried it. Higher octane gas is really only needed for a small minority of cars, typically with higher compression engines. Even then, if they're filled with 87 the car's computer will sense knocking and retard timing a bit.
I tried it, a while back, and my mpg went up 4mpg. However, if you use 10 gallons before refueling, it comes out to less than a gallon of gas saved. The price premium works out to double what you save, so it really isn't worth it, economically...
