Why I feel lose traction when switch from EV to HV?

I swapped from Eco mode to Normal mode to get a feel that is closer to an ICE vehicle. The different modes (Eco/Normal/Power) only affect the scaling of the pedal depression and don't actually impart additional mileage. Eco mode is good for someone that is a bit more "lead footed" and will scale down the effects of that type of driving (thus resulting in higher mileage).

I prefer Normal mode, especially when going long distances as Eco mode requires you to depress the pedal quite a bit further to achieve the same speeds as in Normal. I end up using smaller pedal depressions to simulate Eco mode if that makes sense.

 

The pedal mapping is very different in Hv compared to Ev and, yes, you need much more pedal deflection for the same power in Hv. This is a strange choice by the designers.

 

i prefer to make the decision to switch from ev to hv, rather than have it happen when i'm not aware. one for the reason stated, and two, to do a better warm up while i'm still in ev.

 

Better warm-up refers to what?

Toyota's choice to emphasize the switch was intentional, making the driver well aware of the transition so the subtleties of operation to follow won't be overlooked.

For example, the MPG remains unchanged. You can drive for 50 miles before MPG drops below the maxed out "199.9" value. I did that last week to find out how far I could go on just a single charge before efficiency in HV would actually go unnoticed. 50.6 was the distance traveled, just on my ordinary commute, followed by a run to the coffeeshop. Had I plugged in between, the MPG would have stayed at 199.9 for all my driving that day.

Another thing to keep in mind is that warm-up is more aggressive in Prime than it was in PHV. If I drive my entire commute on just a single charge, the engine will fire up around 33 miles. Shortly after warm-up completes, I notice EV capacity available. This newer system takes advantage of stoplight & acceleration activity. How many owners would notice that, especially if the transition from EV to HV wasn't emphasized?

 

I noticed loss of power also. It drives good in the electric mode but when switches you do not have much power and really have to step on the gas pedal like everyone says.

Posted via the PriusChat mobile app.

 

Interesting. First I've heard that. Citation?

 

Perhaps to give the user that EV performance they want, while attempting to give them better ICE fuel economy.

 

I always use ECO drive mode and too have noticed that when switching from EV to HV I am slightly losing speed speed and need to push harder on the pedal ... interesting read about torque in the manual below.

Question for the more tech savvy: aren't both electrical motors utilized in EV mode? and only 1 in HV mode? Could that explain why i feel a loss of "power" when switching?

 

No.

Both are used in Hv mode too, just differently. The maximum total drive train output in Hv mode is higher than it is in Ev mode.

 

Though the ECO vs NORMAL vs POWER switch works for BOTH EV and HV modes, I think you feel the ECO vs NORMAL difference more in HV than you do it EV. So if you have it set to ECO (as I do), when the EV juice runs out and the car goes into HV mode, as soon as you take your foot off the accelerator for the first time, the "HV ECO" mode kicks in, and you'll have to physically push the pedal in more (the old "mind trick" to help you want to not be as aggressive and thus save gas). I don't know how the difference between EV and HV compare in NORMAL because I always drive in ECO, but yes, you're not imagining it. If it bothers you, then you can always switch to NORMAL once you're in HV, but I've simply gotten used to it...

 

Power and "traction" are two entirely different things.
When the battery gets low enough then ONLY the ICE provides the power or the electric motors proved much less........so yes for a while there IS less power. But that has nothing to do with traction.

 

Nope it's not just you. I know when the juice is gone too. My husband drives us to work on all electric. I'm the one driving who drives home when the electric runs out. It's about at the same place in our commute ever day. It's a define feeling of loss of power. Putting the pedal down ( but not to the metal!) keeps me going at the same pace.

 

I'm just guessing here but I suppose if it was the opposite someone somewhere would claim the car surged ahead (!!!) when the uncommanded transition occurred. So an engineer was tasked with making sure it wouldn't happen then subtracted a little more just to be sure.

 

...if there is battery power available.

One more time...traction is the tires' grip on the pavement. The power put out by the drivetrain is something completely different.

We always switch to PWR mode in freeway traffic. More scoot when an opening appears....

 

While in EV mode both MG1 and MG2 are used to drive the wheels, in HV mode one of the two motors has to generate electricity thus is unable to drive the wheels. Furthermore, during the ICE warm up (S0 phase) the HSD tends to minimize the ICE power output in order to speed up the warm up process and prolong the engine longevity - cold engines do not like high loads and RPM.

 

Full throttle is the same regardless of drive mode.

 

Both motors can be used for propulsion in EV mode. Besides for maximum output, if and when M/G1 spins up to help isn't public knowledge at this point.

In HV mode, you have the ICE to provide propulsion with M/G2(the main traction motor) instead of M/G1. M/G1 is being used though, to generate electricity for M/G2, and to work with the ICE to make the gear ratio changes of the transaxle.

The loss of power sounds to be from a slightly different mapping for the accelerator, but it could be because the ICE has a different torque curve than the electric motors.