Does anyone else think the instant MPG gauge is useless?

I disagree. I find that it is more helpful than any other gauge for me to see if my foot is too far down, AND if letting up a little might be a reasonable thing to do, given the traffic flow.

 

I agree
I has its use
Wouldn't mind other gadges as well

 

I find the instant MPG gauge very useful--for 50 MPG and below. Above 50 MPG it's not very useful, since it's super sensitive in that range.

 

I disagree as I think it is very useful as immediate feedback, especially if I have another screen other than the HSI displayed.

 

It's the easiest way to tell you're gliding. Accelerate, come off the gas, add a little pressure back onto the pedal -- if the gauge goes to the top, you're gliding; if it doesn't, you're adding too much pressure (maybe you're on an upslope; maybe you're too heavy-footed). You can pick all that information up out of the corner of your eye, something you can't say about the other economy displays.

Also, you can tell when the ICE is still cold, because you'll be gliding, but not reaching the top of the "gauge."

 

Like others, I totally agree the guage is extremely useful. I use it all the time to keep my mileage peaked. As a matter of fact, I'm right at 59.7mpg, hoping to hit 60!

I also agree that two other gauges would be very helpful: 12V battery voltage and engine coolant temp.

 

It is useful to me to monitor my current driving. As others have said, it shows what you are doing right now. I do wish that the accumulative MPG figures were more accurate. I record those from the car computer and then my spread sheet makes a calculation based on the actual fuel used & miles traveled and the actuals are always less than the car computer calculates. It really could be closer.

 

Very useful (when using L/100Km instead of MPG) (fuel consumption: gas per distance; instead of the weird US distance per gas measurement).

0 L/100km: Engine is off (at 72km/h or less) or not turning without burning gas (at more than 72 km/h)
2-4L/100km on the highway, going into heretical mode
7.5-10 L/100km: brisk acceleration without going into PWR zone
10 L/100km upper limit: innefficient acceleration into or over the PWR zone, may be anywhere between 10 and ~35 L/100km...

With the instant fuel consumption gauge, I can confirm very quickly when I glide: the indicator falls instantly to 0.

Also, while coasting, I know when the engine is warming itself up (1-2 L/100km) or charging the batteries (~5 L/100km).

Maybe it's only me, but I can't understand the concept of "infinite miles per gallon" when you glide. Totally counter intuitive.

Due to the nature of the MPG beast (US MPG or Japan km/L). Doesn't react this way on the rest of Earth.

 

I look forward to being able to track fuel efficiency as Liter per 100 km or gallon per 100 mi, just like the rest of the world.

 

I agree. I think the instantaneous mpg read-out is what I use most, and is also how I determine when I'm powering off of the battery and not the ICE. .

 

Very useful on the Prius and non-hybrid cars as well, when they are so equipped. I use it in conjunction with the HSI indication and find that combination far better than what we had with the Gen2.

 

I like it. I wouldn't want something that only lights up every 5 years telling me to change the 12v battery.

 

The CONS means consumption.

 

You may already be aware of this but in case you haven't run across it yet - the 12V battery doesn't actually start the ICE. It's function is to power things when the car is in the Acc or On modes, i.e. not in Ready. When you do go to Ready the 12V battery supplies the computer and closes the relays that apply power to the inverters from the traction battery. Once the traction battery is on-line it supplies everything and charges the 12V battery as well. The ICE is started by MG1.

A couple of 6V dry cells in series would do the job with power to spare. In fact you could use them as a backup and just hook them to the jumper connection in the under hood fuse box.

I will probably replace my 12V battery after 4 or 5 years to be on the safe side, I hate to be stranded also. I will most likely use one of these: 12 Volt (12v) Toyota Prius Auxilary Battery for 2004, 2005, 2006, 2007, 2008, 2009 and 2010 with installation kit The OEM 12V battery from the dealers is a rip off.

 

Yeah, like RPM - would be even more useful...

 

I honestly love the instantaneous MPG meter. It helps me see how economically I am driving at that VERY moment. Lets me also see how warmed up my engine is depending on how many MPG's I'm getting. Not to mention, if I'm at highway speeds sometimes I can't tell if my engine is on or off. When I see that MPG meter at 100, I'm for sure it's off. I like it.

 

It's great. It helps me keep my foot off the pedal.