I have had the Prius Prime for a year and now have 10k miles on it. Have loved driving it in pure electric mode no matter whether it is in Eco/Normal/PWR Setting. However, the transition to hybrid mode is always jarring and the performance of the Prime in hybrid model leaves a lot to be desired. So for the last week or so I have been experimenting with driving the Prime on the PWR setting. The # of miles I get from electric only driving is about the same. However, I am finding that the Prime is much more fun on PWR setting when driven in the hybrid mode. I am also seeing a 5+% better MPG on the PWR setting. This seems counter intuitive to me. Anybody else observe this?
Those modes don't really do much, just change the gas pedal travel. I would use whatever's comfortable. My pref with our 3rd gen is "Normal". It doesn't even have a button on third gen, it's just not pushing ECO or PWR. For 4th gen (and Prime) I believe they made them all a bit more aggressive, shifted by about a "mode"?
I haven’t played with it since it is normally in Econ. Wow, PWR is definitely peppy. Normal may be more to my style.
I dont have a Prime, but my Gen4 engine and driving modes are the same. I tried them all, and the PWR mode "feels" the best. I like the lighter-feeling gas pedal, and very little pressure is needed to get the car up to speed. When in ECO mode, I didn't like the heavier & lengthy pedal travel needed to get the car moving. And my gas mileage is always better when in PWR. I just drive my Prius like a regular car. No pulse & glide games. 55-57 mpg driving normally to briskly is good enough.
This is a discussion for prime owner really, only the prime acts like the prime, I agree, if it's not in power mode it's a very different vehicle, but in power mode you can switch from electric to hybrid and there's really no difference in gas pedal input, but it you're not in power mode you have to put the pedal to the floor to maintain speed.
The PWR mode enhances the throttle response (more "go" for the same throttle position). Thus it "jumps" off the line and gets to speed sooner than under a Normal or Eco throttle setting (same throttle position assumed). What I'm trying to say is, you push down on the throttle exactly the same amount. In PWR mode you will accelerate faster and get to cruising speed sooner than the other two modes. Keep in mind, best MPG is achieved at steady cruise as opposed to under acceleration, thus the sooner you get to cruise speed, the longer you will be in the best MPG state. The more time you spend at cruise speed, the better the MPG. As an aside, back in the early '80s under pressure from gas supplies and prices, BMW created the 528e. The 'e' was for efficiency, an early attempt to get best MPG out of current engine technology. The engine was tuned for max torque at low RPM, the exact opposite of other BMW engines of the day which were designed for high RPM operation. Along with that characteristic, BMW advised drivers to use the extra low-end torque to accelerate quickly to cruising speed.
There is another difference from the ECO mode - the A/C works differently in ECO mode versus Normal or Power mode. I've found I get better mileage range on Normal compared to ECO due to the cabin being properly cooled. When on ECO mode only the vents on the driver side blow air (unless you have passengers) and it's just not enough to cool the whole cabin so the ambient temp stays too hot and therefore the A/C struggles and uses more power. Only played with the Power mode when I'm only going to be driving a couple of miles on a full charge so don't know what if any other differences there may be between Normal and Power besides what has already been stated about the throttle.
Which begs the question, is there any downside to using the PWR setting on a long term basis? For example, am I putting more load on a "cold" engine, as opposed to using Eco/Normal setting?
The modes are just changing the amount of gas pedal travel. You can get exactly the same amount of throttle opening, engine response, in any of the modes. And the aforementioned AC behaviour changes, but that's kinda immaterial.
if you are revving the engine more when cold because the pedal is so responsive, that 'could' be an issue, but i doubt it. 'more fun' and 'better mpg's' is definitely counter intuitive. some here claim they get better mpg's in power mode, but not while driving spiritedly. what about the 'jarring experience' in transition?
I was referring to the fact that when I am in the ECO setting and the Prime goes from running on EV to running in hybrid mode, suddenly the amount of pedal travel you have to provide changes to get the same response from the car. This is what I meant by "jarring". OTOH, when one goes from EV mode to hybrid mode in PWR setting, there is less of a difference. The transition seems more seamless.
I would say no downside to always using PWR. The only thing that changes is the sensitivity of the throttle. As has been pointed out, you can get the same throttle input in any mode by simply pushing harder, thus you can stress a "cold" engine in any mode. It's totally a matter of personal preference. How hard do you want to push the throttle?
I'd qualify that a little, not so much "how hard" as "how much travel". And yeah, on 3rd gen (which apparently has the pedal mapped less aggressively, in all the modes) I started out setting it in ECO, sure that if I turned it off, my mpg would tank. I gamely stuck with it for about 6 months, but was finding the amount of pedal travel required to get a reaction maddening. I think there's a certain sweet-spot, a small but adequate movement that's comfortable, considering the average foot size. Increase beyond that, you don't make the driver more conservative/sparing with the gas, you put him into a constant exercise, having to use more of his leg muscles, and always needing to really tromp it. it's a bit counter-intuitive, but I think ECO travel (at least as set on third gen) is ultimately bad for mpg. Or at least for your calve muscles...
A few weeks ago, I made the switch from ECO to normal. It wasn't so much the pedal travel as it was the wimpy air conditioning. And I haven't noticed any change in economy, but then it'll take a long time for enough fill-ups to be sure.
In the Prime, the A/C ECO mode can be set independently of the drive ECO mode. In the PiP (2012-2015 PlugIn), drive ECO mode implied A/C ECO mode. In the Prime, setting drive ECO mode sets A/C ECO mode by default, and setting it to another drive mode turns of A/C ECO mode , but you can override the default behavior in the climate control settings.
Drive modes don't change anything but the throttle pedal curve. If you floor it any mode, it's the same. It's just a sensitivity adjustment. Nothing more, nothing less. The car makes the same amount of power in every mode. Eco just tries to hold you back to avoid any sudden throttle inputs. As said previously, A/C ECO can be toggled on and off independently of the drive modes, it's just on by default in Eco drive mode.
