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Discussion Starter #1
From this video, this guy is testing what happens when there is no gas (and no battery eventually).

At 01:30 in the video, he mentioned that the car doesn't go as fast and it has reduced the performance because the engine is not available; hence he couldn't merge the highway as fast as he could have done otherwise.

https://www.youtube.com/watch?v=vy_7wh0XIa4

Never tested this myself. This is unexpected for me as well since I know the car is and should be a pure electric car and its EV performance should not tie to how much gas the engine has.

Any thoughts?
 

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It's true though. When the gas engine is unavailable my 2017 Volt runs at about half performance. The car switches to Normal mode automatically, the DIC dings with Engine Not Available followed by a "Reduced Propulsion" message. The only thing I can figure out is that GM is putting the car into a low power mode to reduce power consumption on the assumption that you've already run through the normal EV battery buffer and are not out of gas and "out of battery". This will extend the roughly 2KWh of battery to hopefully get you to a gas station.

I find it interesting the Bolt does the same thing when its battery gets low.
 

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Discussion Starter #3
It's true though. When the gas engine is unavailable my 2017 Volt runs at about half performance. The car switches to Normal mode automatically, the DIC dings with Engine Not Available followed by a "Reduced Propulsion" message. The only thing I can figure out is that GM is putting the car into a low power mode to reduce power consumption on the assumption that you've already run through the normal EV battery buffer and are not out of gas and "out of battery". This will extend the roughly 2KWh of battery to hopefully get you to a gas station.

I find it interesting the Bolt does the same thing when its battery gets low.
Even the bolt does it???? This is a bummer.
 

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I agree in theory it should go as fast, but I think the designers throttled it to conserve range when out of gas. In the Gen 1, the power is limited to about 2/3 of the normal maximum. Still drives fine like that, but obviously flooring it will not be as quick.
 

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I believe GM does this to avoid people keeping the tank empty to avoid FMM and EMM... there are some hardy souls out there that do crazy things to keep the engine from ever running, and GM doesn't want to be on the hook for warranty work for engines that have never been run and gas lines full of fouled gas. Basically, they want you to keep the engine and fuel system happy, so PPR is their way of forcing you to do that.
 

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Keep in mind, too, there was no Hold Mode in the 2011/2012 Volts. When those original Volt model year cars ran out of gas for the generator, the only remaining source of propulsion fuel was whatever was left in the battery buffer between the ~20% "switch to gas" state of charge and the ~15% "hard floor, you won’t be able to go lower than this" state of charge. That ~5% of the car’s 16 kWh battery was thus ~0.8 kWh or less, perhaps enough to limp along for 2-4 miles.
 

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Keep in mind, too, there was no Hold Mode in the 2011/2012 Volts. When those original Volt model year cars ran out of gas for the generator, the only remaining source of propulsion fuel was whatever was left in the battery buffer between the ~20% "switch to gas" state of charge and the ~15% "hard floor, you won’t be able to go lower than this" state of charge. That ~5% of the car’s 16 kWh battery was thus ~0.8 kWh or less, perhaps enough to limp along for 2-4 miles.
They had Mountain mode, though, so you could still run out of gas with almost half a battery left.
 

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Wait -- I thought you had to only use more throttle pedal ?
 

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50 kW is about 42% power. That's pretty bad. If they were worried about FMM/EMM, they should just let the car run at full power until the car actually needed FMM/EMM (or the battery is almost dead). No reason to limit power like this when you are nowhere near FMM/EMM and above 2 bars of battery.

Not a big deal (just add a couple gallons of gas) but they could have implemented this better!

Mike
 

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Discussion Starter #10
50 kW is about 42% power. That's pretty bad. If they were worried about FMM/EMM, they should just let the car run at full power until the car actually needed FMM/EMM (or the battery is almost dead). No reason to limit power like this when you are nowhere near FMM/EMM and above 2 bars of battery.

Not a big deal (just add a couple gallons of gas) but they could have implemented this better!

Mike
Exactly my thought. It's the driver's fault for not planning ahead and used up all the available energy of the car and gets stranded. But reducing the power like that when one is not expecting is a user experience (UX) bug.
 

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We have a 2016 Volt Premier. Why take a chance in damaging the Volt's gas engine by not at least running it once a month, and keeping at least half a tank of gas in it. We use our Volt's gas engine more than most, I believe. Overall lifetime per voltstats.net is 48.34 mpg (cs) with well over 16,000 miles on the gas engine of the current 47,000 miles total with gas and electric, and over 141+ mpg combined.

The Gen 2's gas engine is more efficient than most owners give it credit. Our last trip yesterday down the Oregon coast via Highway 101 with all our gear, my wife, and our 90 lb black lab was 126.7 miles total, 64.3 miles on electric with 14.4 KWH used, and 62.4 miles on gas with 1.06 gal's used for 58.6 mpg (reg. 87 octane costco gas), this is the dash readout at the end of our trip in our driveway.

I don't see the pain in using gas even though the gas prices here are perhaps higher than most places in the U.S., currently $3.159 per gallon for reg. at Costco which is the lowest in the area for more than 70 miles...
 

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It's true though. When the gas engine is unavailable my 2017 Volt runs at about half performance. The car switches to Normal mode automatically, the DIC dings with Engine Not Available followed by a "Reduced Propulsion" message. The only thing I can figure out is that GM is putting the car into a low power mode to reduce power consumption on the assumption that you've already run through the normal EV battery buffer and are not out of gas and "out of battery". This will extend the roughly 2KWh of battery to hopefully get you to a gas station.

I find it interesting the Bolt does the same thing when its battery gets low.
Two different things. The Volt goes into PPR and limits pet output when it believes the engine isn't available at any battery state of charge.

The Bolt limits power at very low battery states to protect the battery cells, like every other modern EV I know, including the Leaf (turtle mode) and all Teslas.
 

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I don't understand why anyone is running their Volt out of gas. It's generally accepted as bad for the fuel pump to do this. The car is not meant to be run on empty. I always keep between 1/4 and 1/2 tank in there.
 

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It is not smart to let your vehicle run out of fuel. Modern fuel pumps will not be damaged if there is no fuel in the fuel tank.

Many years back, I was not even 22, I was at a full service station (remember when those existed) and the attendant, an old timer, berated me for letting my 12V battery's electrolyte level get extremely low. I never understood how this had happened as I had checked the battery before starting on a long trip. Anyway, the attendant said something to the effect that I did not deserve a car as nice as this car since I did not take care of it. He suggested I should be driving a kiddy car.
 

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It is not smart to let your vehicle run out of fuel. Modern fuel pumps will not be damaged if there is no fuel in the fuel tank.

Many years back, I was not even 22, I was at a full service station (remember when those existed) and the attendant, an old timer, berated me for letting my 12V battery's electrolyte level get extremely low. I never understood how this had happened as I had checked the battery before starting on a long trip. Anyway, the attendant said something to the effect that I did not deserve a car as nice as this car since I did not take care of it. He suggested I should be driving a kiddy car.
Maybe he couldn't afford the dentist bill to get his front teeth pulled and he was hoping you'd knock 'em out for him?

;)

Mike
 

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I think most electric cars do this. My Leaf did the same thing.
 

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...and in a gas powered car, what happens when you are out of gas?? It doesn’t run at all! At least this way you are able to “limp” to a gas station. GM can’t know when you are going to fill up, this limp mode I think is a good idea.
 

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We have a 2016 Volt Premier. Why take a chance in damaging the Volt's gas engine by not at least running it once a month, and keeping at least half a tank of gas in it. We use our Volt's gas engine more than most, I believe. Overall lifetime per voltstats.net is 48.34 mpg (cs) with well over 16,000 miles on the gas engine of the current 47,000 miles total with gas and electric, and over 141+ mpg combined.

The Gen 2's gas engine is more efficient than most owners give it credit. Our last trip yesterday down the Oregon coast via Highway 101 with all our gear, my wife, and our 90 lb black lab was 126.7 miles total, 64.3 miles on electric with 14.4 KWH used, and 62.4 miles on gas with 1.06 gal's used for 58.6 mpg (reg. 87 octane costco gas), this is the dash readout at the end of our trip in our driveway.

I don't see the pain in using gas even though the gas prices here are perhaps higher than most places in the U.S., currently $3.159 per gallon for reg. at Costco which is the lowest in the area for more than 70 miles...
I also have a 2016 Volt Premier and I too have a casual attitude toward using gasoline. If the car wants to run the engine for Engine Maintenance or Fuel Maintenance or cycle it on and off because the temperature is below freezing, well that's fine with me. During the first year and a half I ran the engine in Hold Mode a lot to get some miles on it in case that there were reliability issues lurking in the ICE. No problems found there. Nowadays I simply charge it up when needed, add fuel when needed and enjoy the ride, while watching the interplay between gas and electric modes. The car seems nicely engineered and is a pleasure to drive. :cool:
 

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...and in a gas powered car, what happens when you are out of gas?? It doesn’t run at all! At least this way you are able to “limp” to a gas station. GM can’t know when you are going to fill up, this limp mode I think is a good idea.
This.

The alternative, in nearly every other vehicle, is being stuck on the roadside, waiting for help. The Volt is not designed nor intended to be operated w/o the ICE being available. It's a hybrid, afterall, and foremost. If you don't want to experience PPR, then don't allow the conditions that force it. The designers didn't have to allow the deep-discharge power available, but they did. I consider this a bonus. They could have simply left you powered off, just like nearly every other vehicle on the road. Just like the "reserve" on older motorcycles, if you run out of gas and get stuck somewhere you don't want to be, it's your fault. The engineers have already done all they can do to protect you from yourself.
 

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I don't understand why anyone is running their Volt out of gas. It's generally accepted as bad for the fuel pump to do this. The car is not meant to be run on empty. I always keep between 1/4 and 1/2 tank in there.
Many car forums I’m on a lot of owners brag how far they go every week with the low fuel light on.
 
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