Eco mode and EV mode

Are you checking instant MPG on your Torque app?

I would very much expect the engine to be showing revs because it is turning, but that doesn't necessarily mean it's being given any fuel to burn.

I guess this is a little easier for me - instant MPG is instant l/100km, so our figure is 0 instead of ∞.

 

When the engine is off my Torque app shows 255 mpgs.

 

We're talking about the situation where the EV indicator disappears, the engine is showing RPMs, but also showing (in my case) 0.0 l/100km, which I guess would show as 255 MPG in your measure.

I believe this was what john1701a was getting at.

 

I've never seen more than 150 mpgs with revs. Not sure what that correlates to in l/km.

 

Engine revs doesn't mean fuel is being consumed. It simply means the pistons are in motion. Prius is optimized for that, allowing air to pass through without compression for extremely efficient stand-by.

 

The revs are above 1000. The car idles lower than that. If the electric motor is having to spin the ICE at faster than idle, it would be inefficient. I don't know either way, I'm just throwing out what I see.

 

Keep the big picture in mind. Overall efficiency can be sacrificed by stopping the engine too soon.

 

But wouldn't it make more sense to just let it idle? Don't have to kill it completely, just let it idle.

 

I misread your post. Sorry.

The electric motor is *NOT* maintaining the spin. That motion comes entirely from kinetic energy transmitted from the road, the result of the vehicle rolling.

 

Then wouldn't it be different revs depending on the speed you were going?

 

It's roughly 1.57 l/100km. Assuming 150 isn't your device's display maximum (which I gather it is not), then this level is still using fuel. For what it's worth, 0.1 l/100km is equivalent to 2352.15 MPG... it's the asymptotic nature of the conversion:

FooPlot | Online graphing calculator and function plotter

I'm going to have to check again next time, but I believe this is my experience, yes.

 

If that works out in your experience great. But I haven't had it happen that way, yet. It usually sits at 1000 revs and stays there until I need the throttle again. But then again, this is at 60-65 on the highway going down a huge hill.

 

When gliding, I go between true glide (no green EV power, no blue regen) and a bit of electric assist (up to half of the EV portion of the bar). Regardless, be sure you're out of the regen range (which requires a very slight amount of pedal pressure) unless you want to be slowing down.

 

Truth be told, is there a difference between the EV mode that shows up on the screen and the EV mode when you push the button?

 

Kind of. EV button tells the car you'd like the ICE to stay off if possible - it's a suggestion. EV light on says the ICE is actually off.

It's possible (I think?) for the EV light to be off and the ICE to be on but not using any fuel - just pumping air.

 

EV mode (button push): Engine cold = 10 mph max
EV mode (button push): Engine warm = 25 mph max
EV mode (no button just light): up to 46 mph max dependent on the engine temperature and throttle position.

 

I strongly suspect we are having the same experience, to be honest with you. In my case my normal driving rarely takes me above the 76 km/h tipping point to the ICE being forced on, so I have very limited opportunities to observe this.

I have though brought up RPM and LHK (the l/100km version of Instant MPG) on the ScanGauge and have today observed 996 RPM and 0.00 LHK coming up at the same time while maintaining an 80km/h speed limit on a downhill.

I'm guessing this really needs observation of MG1 and MG2 to get the entire story here... but the car is undoubtedly capable of having the ICE turn over without giving it any fuel.

 

Would make sense.... if the two MGs are acting as clutches for the ICE and just keeping it spinning at a constant 1k RPM.