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Discussion Starter #1
Is there a way to force the ICE to run at very low speed (like 5 - 10 mph)? I will be crawling around for a while at night and want real heat to be available like it is from the ICE. My experience is that Hold mode just uses battery power at those speeds.
 

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Is there a way to force the ICE to run at very low speed (like 5 - 10 mph)? I will be crawling around for a while at night and want real heat to be available like it is from the ICE. My experience is that Hold mode just uses battery power at those speeds.
If the outside temp is colder than 35F/1.7C the Engine Assist Heat will cycle the ICE and maintain the engine coolant temp between 120F - 140F to heat the cabin. If you have set Engine Assist Heat to Deferred then it will have to get much colder (less than 15F/-9.4C) before Engine Assist Heat will activate.

Engine Assist Heat works well but for shorter trips, i.e. less than 5 miles, the engine may not be running long enough to adequately warm the engine coolant to provide cabin heat. For short trips preconditioning the Volt for 10 or 20 minutes and then using the electrically heated seats and steering wheel is a better option.
 

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Discussion Starter #3
If the outside temp is colder than 35F/1.7C the Engine Assist Heat will cycle the ICE and maintain the engine coolant temp between 120F - 140F to heat the cabin. If you have set Engine Assist Heat to Deferred then it will have to get much colder (less than 15F/-9.4C) before Engine Assist Heat will activate.
This I understand, but I don't think it will even be below 35.

Engine Assist Heat works well but for shorter trips, i.e. less than 5 miles, the engine may not be running long enough to adequately warm the engine coolant to provide cabin heat. For short trips preconditioning the Volt for 10 or 20 minutes and then using the electrically heated seats and steering wheel is a better option.
Unfortunately we will be in stop and go conditions for more than an hour. I may have no choice but to burn the battery down.
 

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Discussion Starter #4
We plan to take in the Seneca Creek Lights Display this weekend. Not having a sunroof for the first time will also be a bummer.
 

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This I understand, but I don't think it will even be below 35.



Unfortunately we will be in stop and go conditions for more than an hour. I may have no choice but to burn the battery down.
Once the cabin heater core has been warmed via preconditioning it does not take that much power to keep it warm. Just set a moderate cabin temperature and Economy mode heat, use the heated seats and remember to dress warmly :D
 

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I think you're going about it the wrong way. If you want real heat like the ICE, just turn up your cabin temperature. You should be able to get the heat to whatever comfortable temperature you want without needing to game the engine.
 

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Discussion Starter #8
I think you're going about it the wrong way. If you want real heat like the ICE, just turn up your cabin temperature. You should be able to get the heat to whatever comfortable temperature you want without needing to game the engine.
You are right. I just have to pay the range price since I won't have anywhere to easily plug in for a couple of days.
 

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You seem to be forgetting that the Volt is programmed to maintain the battery’s state of charge when driving in Extended Range Mode. Driving in Hold Mode shouldn’t run down your battery (beyond the normal fluctuations around the "held" SOC), even when the electric heat is turned up high.

True, in Hold Mode at low speeds, the electric motor’s fuel consumption rate may be low enough to keep the ICE turned off for periods of time (miles powered by electricity but recorded as Gas Miles!), but when electric demand drops the battery SOC far enough below the "held" SOC (whether at the fully depleted level or in Hold Mode at any higher SOC), the ICE will turn on to recharge the battery back up to that SOC.

If you don’t want to switch to Hold Mode with a fully charged battery to "save" all of your battery for other parts of your trip, you could switch instead to Mountain Mode. You would remain in Electric Mode until the battery SOC dropped to the ~2 bar MM-maintained level (Gen 2 Volts), and then your Volt would run the ICE when necessary to maintain that ~2 bar SOC level to be used at other points in your trip, even with the electric heat turned up high.
 

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You cant accomplish your goal. I assume you have a long trip, ie, 100mi and figure you want to run the first 10 miles and final 30 miles on gas to get the coolant nice and hot at first so your heat comes from burning gas and lasts you through the trip, rather than run through your ev miles at the start with resistance heat. But if you don't have higher speed or a hill at the start, it will take too long to get heat from gas. So wear a jacket and don't breathe on the windshield until your are going fast.
 

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You could leave the hood slightly unlatched so the sensor forces the engine to idle continuously.
i.e. pull the release latch, but leave hood closed. Can do it from the cabin, too.
 

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I think you're going about it the wrong way. If you want real heat like the ICE, just turn up your cabin temperature. You should be able to get the heat to whatever comfortable temperature you want without needing to game the engine.
You are right. I just have to pay the range price since I won't have anywhere to easily plug in for a couple of days.
Ahh, ok now your goal is understood a bit more. Based on this response, hold mode is, in fact, what you want to use.

You’re right the engine won’t always be on, but that’s because you’re not using lots of energy going slow. The engine will cycle on and off to maintain your desired state of charge. At slow speeds it will run for a small amount of time, stay off for a longer amount of time, and repeat.
 

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You seem to be forgetting that the Volt is programmed to maintain the battery’s state of charge when driving in Extended Range Mode. Driving in Hold Mode shouldn’t run down your battery (beyond the normal fluctuations around the "held" SOC), even when the electric heat is turned up high.

True, in Hold Mode at low speeds, the electric motor’s fuel consumption rate may be low enough to keep the ICE turned off for periods of time (miles powered by electricity but recorded as Gas Miles!), but when electric demand drops the battery SOC far enough below the "held" SOC (whether at the fully depleted level or in Hold Mode at any higher SOC), the ICE will turn on to recharge the battery back up to that SOC.

If you don’t want to switch to Hold Mode with a fully charged battery to "save" all of your battery for other parts of your trip, you could switch instead to Mountain Mode. You would remain in Electric Mode until the battery SOC dropped to the ~2 bar MM-maintained level (Gen 2 Volts), and then your Volt would run the ICE when necessary to maintain that ~2 bar SOC level to be used at other points in your trip, even with the electric heat turned up high.
This. When I encounter the traffic crawl on I-5 in the Volt, it was in HOLD mode and the ICE would cycle every few minutes to keep the SOC up. The Voltec drive train is very well made, so I'd not worry about it and just engage HOLD mode if you need lots of heat for your drive. I'm sure this off/on cycling is the ideal way to run the ICE else GM wouldn't have programmed the Volt to behave so.

Still disappointed in the engine misfire, but overall, I'm still a big fan of the Voltec. Hope to get one in a SUV or truck form down the road once they perfect it.
 

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I don't know what the complaint is for heat. In both gen 1 and gen 2, if you hit AUTO, COMFORT (MAX), and set the temp at least 74, then it will smoke you out. I do this for maybe 5 min into the drive then I drop the temp down to 69 for the rest of the trip. Never used engine assisted heat, it hasn't gotten below 15 yet. With the way this transition to winter is going in the southeast, it seems like it will be a warmer than average winter.
 

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Unfortunately we will be in stop and go conditions for more than an hour. I may have no choice but to burn the battery down.
Burn it down. Then the engine will come on often enough to keep you warm.

I'm enough of a Grinch to just skip the holiday lights crawl, though. :)
 

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Discussion Starter #17
To report back, all went well. Traveled about 3 miles, used about 10 miles of range, kept sufficiently warm. Fortunately the hotel we were at had an outdoor socket out front that they were happy to let me plug into over night. So range was not the issue it might have been anyway.

No scrooges to be found ;)
 
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