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Discussion Starter #1
Did an experiment last night with battery depleted.
Drove 54.1miles on Normal Mode, cruse set 77mph got 31.8mpg.
Drove 54.1miles on Mountain Mode, cruse set 77mph got 33.8mpg on way back.
But had issue in Mountain Mode. My plan was to use the 14 Electric miles I gain using Mountain Mode. But, when I switched to Normal Mode at 77mph It briefly showed the Green Battery symbol with 14(i think Miles) then went to Normal Mode with gas engine on!
I had to take the damn exit ramp shut the car off then restart, to use the Electric I built up. There by loosing most likely 2-3miles of electric getting back on freeway up to speed.

Is it normal that it will not let you use the electric miles you built up? Pretty stupid programming if so. Or did I do something wrong (stupid operator)?
 

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I have never experienced that. The only thing I have noticed is that you can't go right from mountain mode to hold. Every time I've switched from MM to normal, the engine turns off as long as I have sufficient charge. That includes from a fully depleted battery. This applies to my '13.
 

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After 5 years of ownership with my 2011, pretty much just put it in D and go, but I do recall some discussion of what you are describing. Which is why " Hold " came out on later MY's. It may have something to do with switching mode at 77 mph.
 

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Could be just a one time glitch. Volts seem to experience things like that occasionally.

Given that your first leg included a warm-up cycle for the engine, that would say the two modes are pretty similar for fuel economy.

That being said, if this was an "out then back" trip, altitude differences and wind direction could play a part in biasing one way or the other.
 

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If you drain the battery down to nothing, then turn on mountain mode, it will do this. But if you hit mountain mode before the battery is drained, you can flip from mountain to normal. But then comes the question of why bother. If you out were truly in the mountains then hit flatlands, then OK, but if you were trying to game the system to get better fuel economy, you are really better off leaving it in N for the whole trip. There were some long discussions about a year ago where a forum member tried to define a new term (known as the V-word because if you said the word, it would cause the thread to get closed). It got downright ugly, but it really comes down to conservation of energy and the fact you cannot make something out of nothing.
 

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Discussion Starter #6
Thank you LLninja for explaining that. Next time I should NOT let the range go below say 2 ev miles before selecting Mountain.
As for why bother my test; I was hoping that if in a hurry -77mph- the extra load would not have as much effect on fuel mileage in Mountain as in Normal. It actually seam to be 2mpg better;But; I think a little bit more if i did not screw up the Mountain mode trip back by taking an exit and messing around trying to figure out how to get back into Normal.
 

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Thank you LLninja for explaining that. Next time I should NOT let the range go below say 2 ev miles before selecting Mountain.
As for why bother my test; I was hoping that if in a hurry -77mph- the extra load would not have as much effect on fuel mileage in Mountain as in Normal. It actually seam to be 2mpg better;But; I think a little bit more if i did not screw up the Mountain mode trip back by taking an exit and messing around trying to figure out how to get back into Normal.
It has more to do with KWs left, need about .6kwhr or no dice can occur.

For me this usually means 4 or 5 miles on the guess meter, switching to hold or mountain after that the battery becomes unavailable
 

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Thank you LLninja for explaining that. Next time I should NOT let the range go below say 2 ev miles before selecting Mountain.
As for why bother my test; I was hoping that if in a hurry -77mph- the extra load would not have as much effect on fuel mileage in Mountain as in Normal. It actually seam to be 2mpg better;But; I think a little bit more if i did not screw up the Mountain mode trip back by taking an exit and messing around trying to figure out how to get back into Normal.
Are you sure there wasn't a change in temp or altitude between the trip there and the trip back? I have attempted to test the Volting (there I said it, thread will close soon) and have NEVER gotten better overall MPG using mountain mode vs. normal. With my 50 to 65 mile round trip commute as well as several highway trips to O'hare airport and back (120+ miles one way) I've had plenty of opportunities to test this out. I can see that maybe with long stretches of hills, you might be able to game the voltec system to your advantage, but in completely flat Illinois over hundreds of miles, mountain mode vs. normal mode doesn't make much difference.

In fact the number of times where I played with Hold mode trying to eek out range and left EV miles on the battery as I arrived in at the garage caused me to stop that habit. I've driven home before forgetting that I set it on hold fully intending to switch and arrived with 30+ miles on the guessometer. So after 2 years of playing every game in the book, I now just drive, stopped driving like a grandpa, and just enjoy the ride.

If you really want to see increased range, try driving 70 mph, 65 mph, or 60 mph instead of 77 mph.
 

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Did an experiment last night with battery depleted.
Drove 54.1miles on Normal Mode, cruse set 77mph got 31.8mpg.
Drove 54.1miles on Mountain Mode, cruse set 77mph got 33.8mpg on way back.
But had issue in Mountain Mode. My plan was to use the 14 Electric miles I gain using Mountain Mode. But, when I switched to Normal Mode at 77mph It briefly showed the Green Battery symbol with 14(i think Miles) then went to Normal Mode with gas engine on!
I had to take the damn exit ramp shut the car off then restart, to use the Electric I built up. There by loosing most likely 2-3miles of electric getting back on freeway up to speed.

Is it normal that it will not let you use the electric miles you built up? Pretty stupid programming if so. Or did I do something wrong (stupid operator)?
Your Gen 1 Volt is operating as designed, if you view the usage screen with the understanding that:

Electric Miles/km = distances driven using grid electricity from the battery and any regen that was captured while driving in Electric Mode, and:

Gas Miles/km = distances driven on battery power using battery power obtained from Mountain Mode recharging and from regen captured while driving in Extended Range Mode, plus distances driven while the ICE is running.

When you stopped the car and turned it off and back on again, it confused the accounting system, and even though distances might then have been recorded as Electric Miles/km, the kWh Used number did not change (it’s tracking net grid consumption, grid used less regen obtained).

Note: LLNinja is referring to a glitch in the 2011/2012 Volt programming - switch to MM before ev range is 0, then switch back and the display returns to Electric Mode. Doing this on those models counts MM battery distances as Electric without changing the kWh Used number (2011 Volts had no kWh Used display). This glitch was said to be corrected in the 2013 and later models. All model years seem to be able to count MM battery miles as Electric miles if you turn the car off and back on again, but that just means you have more electric miles without increasing the kWh Used (whee! Increased miles/kWh!), and fewer total gas miles on the trip to be divided by total trip gas used (boo! Fewer gas miles/gas used = lower MPGcs gas mileage).
 

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Your Gen 1 Volt is operating as designed, if you view the usage screen with the understanding that:

Electric Miles/km = distances driven using grid electricity from the battery and any regen that was captured while driving in Electric Mode, and:

Gas Miles/km = distances driven on battery power using battery power obtained from Mountain Mode recharging and from regen captured while driving in Extended Range Mode, plus distances driven while the ICE is running.
Wordptom nailed it. A common misconception is that filling up the battery via the ICE by burning gas should be counted as electric miles rather than gas miles. They aren't. They are gas miles and the battery icon will not display.
 

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But, when I switched to Normal Mode at 77mph It briefly showed the Green Battery symbol with 14(i think Miles) then went to Normal Mode with gas engine on!


I think there is some confusion here. It doesn't appear that the OP is concerned about the accounting screen depicting EV/gas miles but rather an issue where the ICE turns on when in normal mode with significant battery available after having run MM to gain those miles. His concern is that the electric range available isn't being used because the ICE continues to operate maintaining the charge even though normal mode is selected.
 

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I think there is some confusion here. It doesn't appear that the OP is concerned about the accounting screen depicting EV/gas miles but rather an issue where the ICE turns on when in normal mode with significant battery available after having run MM to gain those miles. His concern is that the electric range available isn't being used because the ICE continues to operate maintaining the charge even though normal mode is selected.
Good observation. Thanks for bringing this up, but again, it’s working as designed. The OP drove until his battery was depleted, i.e., he had used all the available grid power stored in the battery. Recharging via Mountain Mode doesn’t change that. He can’t drive in Electric Mode again until he recharges to put more grid power back in the battery, so the car continues to use the ICE. What MM did was to create a battery buffer for use if needed to maintain performance under high demand conditions, such as driving fast uphill.

When the OP turned the car off and back on again, the computer then recognized the battery state of charge was above the "minimum" setting, and so allowed the car to run on battery power and likely counted it (wrongly) as Electric Miles, but because it was not grid power, did not increase the kWh Used number.
 

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Wordptom, I have to respectfully disagree that the car won't allow you to deplete the battery a second time if there is stored energy due to the use of MM. I do it very regular when I drive between home and LA. There is a large grade known as the Grapevine that offers lots of regen and requires MM to climb. On both the down and back drive I use MM to get up the grade and use normal mode on the downslope to take advantage of the available buffer that's no longer needed. I begin the trip from home with a fully charged battery, engage MM and drive in EV until it reaches the MM set point at which time the ICE engages (normal operation as designed). Make 2/3 of the drive in MM until the descent into the LA area where I press the mode button to go into normal. Engine turns off (again, as designed) and does not turn on again until my GOM reads 0 miles. On the return trip, I start out with 0 miles on the GOM since it was depleted on the drive into LA and has not been plugged in, engage MM while in LA and by the time I hit the climb out of LA I have built my buffer back up and maintain MM until I begin the descent into the central valley again engaging normal mode with the MM buffer. According to how I understand the OP, this is the point that his ICE STAYS ON. Mine however acts as before, turning the ICE of and again allowing me to drive nearly home (about 40 miles) with the additional 20 miles or so what buffer MM created as well as "free" energy through regen from the descent returning home. My ICE turns on about 5 miles before I get home.

I believe the OP is concerned that he is unable to tap into any of the buffer that MM created when switching back to normal mode without turning the car off and back on and my personal experience confirms that his experience is different from my personal experience. Perhaps it's a programming concern (different year?). The OP unfortunately left out what year Volt this is affecting, but I can say for certain that my '13 does not exhibit the same symptom.
 

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Discussion Starter #15
Freshcut - It is a 2013. Good to hear your route and that you can switch back and forth and you also have a 2013, it must be me.
All - It was a TEST to see if MM would be better at higher loads/speed than Normal Mode. I know I should drive slower.
I will try leaving a few E miles in if I try this again.
It has been a car for my wife who mostly uses this car to go back forth to work and has been great as she uses all electric compared to the 17-21mpg car she had before.
 

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My 2015 does the same thing. After depleting the battery, I put it in mountain mode for a descent, knowing that I'd be hitting stop-and-go traffic at the bottom of the hill. After putting it in hold mode for awhile, I tried to put it in normal mode and the ICE came back on. I've tried this several times and each time it's worked the same. If I stop and re-start, then it will drive on battery power.
 

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My 2015 does the same thing. After depleting the battery, I put it in mountain mode for a descent, knowing that I'd be hitting stop-and-go traffic at the bottom of the hill. After putting it in hold mode for awhile, I tried to put it in normal mode and the ICE came back on. I've tried this several times and each time it's worked the same. If I stop and re-start, then it will drive on battery power.
My 2013 does the same thing, so the previous post that this happens only with 2011-12 is not right. The fix, don't try to game mountain mode. I just use D and Hold and never go into mountain mode because there are no mountains in flat Illinois.
 

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I believe there was a post within the last month or so where WOT or somebody smart pointed out that there wasn't any way to faithfully determine the battery level while the car is running. To me that suggests that if you run it down all the way and recharge using MM, that you may have to turn it off for a bit so that it can calculate the level of charge.

I think physics suggests that there would be no way under any conditions where charging it while driving would be more efficient than just driving it. I would assert that the cost of charging while driving is probably not all that much more than driving it, but it would always be added load on the ICE. There is also some post or news item somewhere saying that the ICE may engage with the drivetrain at over 70MPH.
 
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