Half/full gas tank?

i've been running 2-3 gallons for many years now. no problems so far

 

You don't own a Prime. It's not the same.

 

are primes worse?

 

Since the system is sealed, there is no way for condensation to build up. As for ethanol and filling it full, makes no difference. My wife and I have been filling our 2017 Primes with E10 since the day each was purchased. No big deal. The tank lasts months and there has never been any reason for concern at all. On one trip to Wyoming from Minnesota, I even filled up with E15 in South Dakota.

 

Count on ethanol free gas lasting roughly 6 months until it goes bad. Take your average hybrid miles per day multiply by 180 & that's the max gas range you should have in the tank. If you only drive 3 miles on hybrid daily, the maximum you should keep in the tank would be 3.5 gallons or so. And that's ethanol free gasoline.

E10 gas is a little dicier. Government says it'll last for 3 months before going bad. But I've heard others say it starts going bad in a month.

Ethanol free gas is definitely the way to go if you are primarily using your prime as an EV only going a few miles a day by hybrid.

I drove my prime home from nebraska arriving with about half a tank, I am pretty sure it's e10 gas, and only drive a few miles a day with hybrid. So I drove with gasoline until I'd bled it down to about 90 miles of hybrid range before commencing my drives with EV primarily. When I get down to 60 miles range, I'll put a gallon of ethanol free gas in it and continue until down to 60 miles or so again. After a few iterations of this, I may put a bit more ethanol free gas in the car. Lower ethanol in the gasoline slows the degradation. I figure when I'm down to E1 or so, I'm in decent shape.

I've heard people on the forum say they're using e10 without problems. Good for them. But if you're primarily an ev driver I'd be careful not to harm your engine with the stuff going bad.

 

E10 has been supported since the first Prius. No big deal. In fact, that has been "gas" for everyone in Minnesota since then. Throughout the 90's it was the winter formula. So, anytime someone brings up a misconception, I just roll my eyes. It works fine and has for millions of vehicles here.

E15 is still rare, but mandates pushed automakers to support it. Toyota does in our 2017 Prime.

 

The PHEV industry designed their sealed tanks to keep fuel good for a year:

Autoblog: How desiging the Chevy Volt's sealed gas tank brought automakers, CARB together

"... but now we've got the scoop on the gas tank used to keep liquid fuel in the Volt from evaporating or going stale for up to a year.

The original Plug-In Prius called for adding at least a certain amount of fresh fuel every 6 months. The Prime lengthened that to once every year.

 

Good to know about these things if my commute drastically changes in the future but my current job has me doing 500-1000 miles per week (depending on the semester) and even with the Prime’s exceptional efficiency, no gasoline sits long enough in my tank to degrade. But the car will go to my daughter someday and she’ll likely have a use case where gas may sit for a long time, so this info is quite useful.

 

We have some Prime drivers here who don't burn a full tank in a whole year. And references to non-PC Prime drivers who burn only a small fraction of a tank per year. They have not yet reported any significant level of stale fuel problems.

 

i never saw any reports with the pip either. toyotas cautions are probably extremely conservative.