Hi there. We bought our 2020 Prius Prime in August 2019 and by mid-December, we'd only used 1/8 gallon of gas. This is because we mostly use it around town. It occured to me that perhaps not using any gas could be a problem so I starting setting it for hybrid mode. Now down to 1/2 a tank. Questions: 1. Do you think I should make sure to use a certain amount of gas so it doesn't get too "old" and to "exercise" the engine. 2. Should I fill it up now so as to mix the old and new gasoline? Thanks.
1. The car will automatically start the engine after a predetermined period of time at just EV mode. The gas tank is sealed so I wouldn’t worry too much about the gas. 2. If you get a lot of extreme temperatures like hot during the day and cold at night it would help to keep it topped off to keep moisture from condensing. But again the gas tank is sealed. Most gas gets old from 2 things temperature and air exposure. iPad ? Pro
Unless you use less than a tank full of gas every 6 months, you should not have to worry. With your location, you may be forced to turn on the gas engine when it's very cold to provide heat. I actually manually turn on the gas engine to provide more heat during winter. The electric heat pump is very efficient but not a very strong heat source when it's cold and below 14F not functional. Just keep driving. You should be fine.
Air is not the only thing that causes gas to "go bad". Some of the components just naturally deteriorate over time. Toyota seems to think that adding a half tank every 6 months is enough to prevent problems. That personally makes me nervous. I would want to see the whole tankful (mostly) replaced at least every 6 months.
Thank you! About #1, I drive the car ~20 miles a day and then charge it every day. Unless I turn on the defrost, I've gone weeks without the engine being used. That seems different than what you describe. Thanks. Leah Thanks! Appreciate the input! I'm finding the manuals kinda miserable to wade through so this chat is super helpful!
With about a half tank used in 6 months, you are ahead of the minimum called out in the Owner's Manual:
rather than add gas, i would use up the remainder by the end of july, then only add what you think you'll use in 6 months. i only add 3 gallons at a time, unless i'm going on a trip.
Oops. I thought it was 6 months. Maybe that is the interval where the gas engine will run a bit to use up some gas. Only putting in just about half the total capacity in 12 months would definitely make me uneasy. Especially if you did that for multiple years in a row.
Leah, if that was my situation I'd add a suitable amount of gasoline stabilizer for a full tank according to the label directions, top off the tank, and rest easy. When you run the engine, do plan on running it for 20 minutes or more to get all the parts fully warmed. Either don't run the engine or try to get it fully warmed. Short, cool running periods aren't the best for the engine.
Go Big Blue! I don't worry too much about gas and do much like Bisco does by adding $10 of gas every 3 or 4 months after the gas gauge falls below 1/8 . Others have posted here of driving several thousand miles on one tank. I'll bet they were not too concerned with how long it took for the tank to empty, I know I don't worry about it. If you plan to take a several hundred mile trip, I would start slow and ramp up the use of the gas engine. It give the gas engine time to settle into a routine and gives the computers time to adjust to the newer sensor data. But it's not necessary to prepare for longer trips as the Prime just works right out of the box. It may make the longer trip more economical, especially if the cars been in EV mode almost exclusively for months at a time. and Welcome to Prius Chat
I always seem to have a long trip now and then that keeps me from going too far on one tank. In fact, I just filled up yesterday after only about 1,200 miles because I'd had two trips across the state. My longest distance between fill ups was 2,615 miles over nearly four months. If not for those trips I'd probably be close to 4,000 miles and 8 months or more per tank and have similar concerns. All that to say, if you use the Prime for trips as well as commuting (and that's the whole idea of a plug in hybrid compared to a BEV), you'll probably use up a tank in a reasonable time and not need to worry about gas getting stale in that well sealed tank.
Thanks for this thread and discussion. Really appreciate the knowledgeable users in this community sharing their experiences and insights. In the year and a few days that I have had my Prime, I've put on around 6800 miles and used half a tank of gas (from the original fill up at the dealership). Probably a good time to watch for a sunny day and take a road trip to burn through another quarter of a tank and then fill up with fresh gas.
