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I just got back from a long round trip Boston to Pittsburgh ... 1220 miles round trip. my 2016 volt was flawless ... we got 45.9 miles (avg) for the trip (had a full charge going there, and one full charge coming back).

Here's my question: on some huge downhill slopes in Pennsylvania (2-3 miles steep downhill), I had the car in HOLD and the display shows the car regenning electricity, but the display showed *no* change in the battery capacity (no increase in miles). Later in the trip, I switched to NORMAL mode and in another long downhill, the battery capacity jumped up an additional 3 miles ! Is HOLD scrubbing off the electricity and converting it to heat? Or is it just somehow not showing that the charge is increasing? (I realize it's a guess-o-meter after all). Just thought this was curious.

Another interesting thing I noticed ... if I drive the volt around 55-60 mph, I get a slight 'chuggle' kind of feel from the ICE. But once I increase speed to between about 65-75+ mph, the ICE smooths out almost completely ... kinda odd?
 

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For a Volt, Electric Miles are miles driven using grid power stored in the battery (used to compare AER and kWh/mile stats with other electric cars). Gas Miles are miles driven when the ICE is running or when using battery power put there by MM recharging.

Regeneration also puts power back into the battery. Using it counts as Electric miles if it was put into the battery when driving on grid battery power, or as Gas miles if put into the battery when driving on gas-generated power (in Hold or MM mode or with fully depleted battery).
 

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Is HOLD scrubbing off the electricity and converting it to heat? Or is it just somehow not showing that the charge is increasing?
Pretty sure it's the latter. Unless the battery was fully charged at the time.

I've previously read that Gen 1 Volts are capable turning regen power into heat when the battery is completely full (even higher than a "full" charge from the grid). Not sure if this is still the case with Gen 2 tho.

In my MY2013, I do notice that sometimes in Hold mode the EV range display will add or subtract a mile depending on the driving conditions, such as a steep hill, particularly soon after engaging Hold mode when the engine is in its "warm up" period. This will result in either a green or red bar at the top of the greyed-out battery capacity display/icon (red if a mile was lost, green if added). So assuming that Gen 2's operate similarly, I would have expected the same behavior. But maybe Gen 2's work differently in this regard.
 

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Is HOLD scrubbing off the electricity and converting it to heat?
No. Any regen that is occurring during Hold is increasing your MPG. Any excess regen will reduce the amount of time or RPM that the ICE must run.

Another interesting thing I noticed ... if I drive the volt around 55-60 mph, I get a slight 'chuggle' kind of feel from the ICE. But once I increase speed to between about 65-75+ mph, the ICE smooths out almost completely ... kinda odd?
Refer to the thread on the Gen 2 chuggle.
 

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I put my 2017 on hold the other day to save 2 miles for my last 2 non-highway miles and by the time I got off the highway they were gone. Is that normal?

ChuckJ
 

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I put my 2017 on hold the other day to save 2 miles for my last 2 non-highway miles and by the time I got off the highway they were gone. Is that normal?

ChuckJ
Mine seems to use a mile or two when in hold mode. Doesn't seem like it ever adds any miles, even if I regen a bunch in hold mode and then switch into normal mode. I've found the behavior a bit curious. I am sure it isn't wasting energy, but sometimes I wonder exactly why it does what it does. Definitely has very different logic than my Uncle's Ford Cmax as to when it's recouping energy, when the engine is running, and when it uses battery power. At the end of the day, I'm exceeding both the CS mileage and battery mileage, so it clearly works. Now if I could just get rid of that chuggle...
 

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Discussion Starter #7
I put my 2017 on hold the other day to save 2 miles for my last 2 non-highway miles and by the time I got off the highway they were gone. Is that normal?

ChuckJ
I don't know if it's normal, but I've seen it too ... best I can tell is: even in HOLD mode, when you are starting from dead stop or at low speed, it DOES use purely electric to get moving from start until the ICE takes over ...
 

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I put my 2017 on hold the other day to save 2 miles for my last 2 non-highway miles and by the time I got off the highway they were gone. Is that normal?

ChuckJ
It is normal. Remember it is an estimate. It takes some energy to start the car. If you wait too long to start Hold mode it may go to zero and you don't have the charge you thought you did. I usually hit Hold 4 miles from home to avoid this.
 

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It is normal. Remember it is an estimate. It takes some energy to start the car. If you wait too long to start Hold mode it may go to zero and you don't have the charge you thought you did. I usually hit Hold 4 miles from home to avoid this.
Thanks for the feedback everyone. Yes, I'll start using 4 miles.

Chuck
 

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It is normal. Remember it is an estimate. It takes some energy to start the car. If you wait too long to start Hold mode it may go to zero and you don't have the charge you thought you did. I usually hit Hold 4 miles from home to avoid this.
To add Hold mode doesn't precisely hold the battery state of charge. It allows some tolerance and mild variation in SOC. So if trying to hold with only 2 miles showing if you switch back and the SOC is on the low end of tolerance I could very well see the car being near the charge sustain threshold.
 
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