Could be both ambient and engine temp. When the engine's warmed up odds are not bad. But with cold engine, there's enough potential vetos to successful EV mode that I've given up on it. If I'm trying to get the car from garage to adjacent driveway, I don't even bother trying the EV button: just start up and quick like a bunny slam into reverse and start backing out, all the while counting seconds in my head. I'm counting on the roughly 15 second grace period before engine kicks in. When I get to 12 or so I shut down, repeat as needed.
So, I suppose Gen 4 EV mode will send an electric shock to the START button for those of us trying to exploit the 15-second grace period.
There's beeping sound during the grace period, and I swear the pace of the beep picks up, as you near the ~15 second threshold. It reminds of Sonic the Hedgehog on a level with an underwater level. He will eventually run out of air if he doesn't get through it fast, and the music reinforces this: building intensity as his air runs low...
I've never heard a beep like that. Sure, it beeps when you reverse, but that's just Toyota's way of reminding you that you have engaged reverse gear. Or it's the seatbelt beep. Never have I heard a beep warning me that the engine is about to be started. I know there are regional differences, but for a european Prius there is no problem pushing the EV button just after starting and it will stay electric until the battery runs out, you exceed 34 km/h or accelerate too quickly. The only things preventing going into EV right after starting is low coolant temperature (really low, like 0 degrees celcius or so) or low battery.
There was a lot of testing done years ago that proved PWR mode gives the highest mpg's. I have no idea how to find that thread though... The electric torque ramps up faster in PWR mode but the total electric motor torque is the same in all modes. Many other vehicles that have ECO, Normal, and Sport mode will respond the same way with higher mpg's when run in the Normal or Sport mode. My Kia Soul does that in Normal mode. My wife's Optima SX turbo does that in Sport mode. My Prius runs higher mpg's as measured on my Scangauge II by running in PWR mode. Some might say I only have 1700 miles on my car, but I have a good 30k miles in rental Prii since 2009 and have been experimenting with the modes Mike
I'd be interested to read that. It totally contradicts what Toyota says and you're mentioning changes in things Toyota does not. The only thing Toyota says that changes is the mapping of the gas pedal, the output of the A/C and the maximum speed of the interior blower. Maybe PWR mode makes it easier for drivers to be in the sweet spot for optimal economic acceleration, but again, that would only be a case of not pressing the accelerator far enough in ECO mode.
I wish I knew how to link to that old thread. Maybe some of the way back when members will chime in with that info. There were charts that showed the torque curves for every mode. The maximum torque and hp never changed but the PWR mode torque curve rose sooner and faster than the other modes. This was tested with the original software before the extremely tame version came out in 2013 I believe. I don't know if the latest software allows the torque curves to be different.
I use power mode on a highway. Very useful when you need to get and change lane quickly. Almost got caught by a semitruck due to eco mode slow response to acceleration. So be very careful in the highway using eco mode. After that incident I always switch on my power mode before getting in the highway. I will not take my chances again before I get cut into half by not using the power mode.
I don't select anymore "mode" anymore after driving with my Prius after 4+ years, I played with ECO/PWR during the 1st year of ownership, but I still like the "normal" mode, I live in the Peninsula near San Francisco bay area, I doubt I get over 50MPG, I am lucky I get 45mpg mixed driving, especially going San Francisco, the mpg dropped 4-5 mpg. My commute to work on highway 101 S mostly stop and go. I average 45mpg calculated (not the MID display MPG).
I stick with Normal. Dealbreakers for PWR: 1. You have to select it every time you start the car. 2. Throttle response in Normal seems fine.
Tried PWR mode. HATED IT. Notable changes.... 1. A/C worked almost full-bore (Auto did make it slow down as the car cooled off, but much more power to the cooling system than on Eco). 2. ICE on almost all the time until motor well warmed up. EV mode almost required hitting the brakes. More inclined to go to EV mode after car was driven for about 15 minutes, but you pretty much had to let off the gas. 3. Never does the "Eco" badge on the HSI ever light up, even if you're in the Eco zone. 4. Where I'd get 70-80 mpg going home (lots of downhill coasting), I only got 65 mpg (based on trip computer). The only positive I could say was I had very peppy and responsive acceleration, but for the cost in gas mileage, it wasn't worth it for my evening commute.
WE0H indicated that the thread is question has proof. I don't see any proof in that thread. Yes, some folks do better in PWR mode than in ECO or Normal, we have known that for a very long time. But that doesn't prove that it inherently produces better MPG than the other modes.
What you just said doesn't make any sense. You're basically saying people do better in PWR mode but it doesn't proof PWR mode gets better MPG. It's like saying some people know that 2 is 1 + 1 but that doesn't prove that 1 + 1 = 2. What kind of proof are you looking for? scientific proof? mathematical proof? DNA proof? I mean real world proof is in that thread. Is that not good enough?
The best I got was 3.7 L per 100 Km (63 MPG). The best way to drive is not related to the mode you are in but driving according to the visible terrain in front of you. Pulse and glide using EV in lower speeds and no ICE glide (ICE is off) in higher speeds.
I suppose the better thing he should have said is that for how SOME people drive, PWR give better results than ECO or regular. I'm not sure how, but I suppose there are some ways it helps. 1. If you are wasting gas trying to get to velocity by going easy on the gas rather than hard acceleration (something they point out about "pulse and glide"). 2. Having a commute where ECO and normal offer no advantage because you effectively can't P&G as you need to in order to gain the benefit.
