I have a 2018 Three Touring and I've been wondering why my gas mileage has been lowering even while cruising slowly in EV mode? I just ran a test in my neighborhood and found this out. Is it normal..?
Was the EV light actually green during all of this? Pressing the EV button, or keeping the accelerator in the EV range, doesn't necessarily mean the ICE is off.
Forget about the Hybrid System Monitor , and instead put up the Energy Monitor - it's far more accurate than the green EV light which can be very approximate at times - almost fiction. You've got part of the System Monitor in your HUD anyway. But the Energy Monitor as below shows clearly where energy is flowing, and whether the Internal Combustion Engine (ICE) or Electric Motors are doing the driving - or both. BUT - trying to drive in EV can be counter-productive, as you might end up having gone to great pains to keep it in EV mode, then it gets to a place where it would "logically" select EV Mode, but you've got no battery left, so it starts the ICE to boost the batteries. Some of my best l/100km readings have been where I've not taken much notice of what's going on, and some of the worst were where I was reallllly trying. TOYOTA has put a lot of effort into automating the system, so, in many cases, "just drive it" is often the best option. If you're on a long run and the road is relatively quiet traffic wise, you can try hypermiling - it can give better l/100km, but best not to annoy other drivers if the traffic isn't light. The other thing to consider - if say you compare with a Civic/Corolla/Impreza, using 10l/100km, it would cost $2250/yr in fuel, and your PRIUS at 4l/100km costs $900/yr - ie save you $1,350/yr. If you manage to eke out another 0.3l/100km, you're going to save another $67/yr - which, in the scheme of things is barely worth it. Search for hypermiling in PriusChat - it is a very good description.
If you drive only in EV mode, the battery will drain quickly, within 3/4 of a mile, and then the battery keeps having to charge up. My understanding is that EV mode is best if you are going very short distances, like moving where your car is parked, etc, and not a mode to be used for a regular drive. I have found the mileage to be best if you let the car manage itself when it uses battery (EV) and when it uses the gas.
Welcome to PC! @john1701a has a website with a boatload of helpful stuff. You might find this guide informative. John's Stuff - Toyota Prius User-Guide. It's Gen 3 focused, but the principles are the same for the Gen 4.
Oh it was definitely on, I did this for testing purposes with a near full battery after noticing that I was losing mileage even while the energy monitor was telling me that the battery was supplying the power. I do realize that ICE uses a fair amount of fuel to start itself, but I noticed whenever it kicked on, the mileage would usually drop another number relatively quickly, so I went ahead and tested it. This was with the A/C off as well. You guys were pretty prompt as well though, thanks!
A good test of this for me is watching what my wife gets when she drives it because she doesn't understand how it works. I tend to hypermile and manage to get quite a bit more than she does and she doesn't have a heavy foot. For me, it's not necessarily about the extra $ savings (though it is nice), it's more of a fun challenge for me to try and eke out more MPG which forces me to understand better how the car works.
Yes, it's a fun game. In years past, my wife and I would often drive each other's cars - I would consistently get a little better economy (though I'd never tell her), even though we drove similarly - if anything, I'd push it a bit harder, though both of us keep to speed limits and not have a heavy foot. I think understanding how things work changes how you drive - back in those days, I could envision the accelerator pump and the throttle plate opening, the action of the clutch, the gears synchronising etc etc as I drove. She drove for results - getting there. Which I guess is the aim of the game. With PRIUS - it's less that I understand as I drive, as it's not just vaporised fuel, ignition and the mechanics of the engine - but little electrons in multiple environments (computer and motive power) as well. But I try.
I found this - I thought it was on PriusChat, but no: Tony Schaefer on Hypermiling » What Drives Us
My 2 cents worth is to just drive it like it was an ordinary ICE car with lots of bells and whistles. You should find the car is smarter than you thought and will deliver good mpg without too much promoting. There's no real secret, just accelerate slowy where possible and brake as gently as conditions allow. Prepare to be amazed!
