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Discussion Starter #1 (Edited)
I got out of work today and it was about six degrees Fahrenheit. I started my car and the motor came on instantly. I knew that would happen. What surprised me is that while I was waiting for the heater to warm up I had an idea. I hit the gas pedal, honestly not expecting a damn thing, but to my surprise the motor reved up more. Not like a normal ICE car but it did rev up higher. I was able to make it rev up enough to start putting electricity back into the battery. I didn't know you could do this. So for any of you who didn't know now ya do.
 

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Whenever the engine starts up, I don't sit there and warm it up like you did. I just put the car into drive and go. When the battery has warmed, it will jump back into service. Until then the ice will supply eneoughnuice to drive the electric motor.
 

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My glass was iced over and I wanted to be anywhere but my work otherwise I would normally just drive so that my MPG number doesn't dip so much. Up to 109 lifetime btw
 

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Interesting. No idea it would work that way but it makes sense. That it revved doesn't surprise me, and, if it revs and you're not moving, it doesn't surprise me that the generator charges the battery. Normally I wouldn't think to do that in the Volt.
 

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My glass was iced over and I wanted to be anywhere but my work otherwise I would normally just drive so that my MPG number doesn't dip so much. Up to 109 lifetime btw
Yeah, I used to drive like a grandpa to keep my mileage up, but no more. I just drive and have fun taking on pony cars at stoplights.
 

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Interesting. No idea it would work that way but it makes sense. That it revved doesn't surprise me, and, if it revs and you're not moving, it doesn't surprise me that the generator charges the battery. Normally I wouldn't think to do that in the Volt.
So I wonder if someone could fabricate a switch that does the opposite of th ERDTT defeat plug to trick the ice to come un upon startup, allow you to rev the engine to charge up the battery? I'll have to try this next time my engine starts right up because thenbatery is too cold to be used right away.... not to gain any EV miles, but in the interest of science
 

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I believe this is normal if the battery is too cold. The engine supplies all power until the battery's temp is high enough to supply power.
 

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I believe this is normal if the battery is too cold. The engine supplies all power until the battery's temp is high enough to supply power.
The holy sh#t part wasn't because the ice started, but tha fact that revving the engine added a battery bar...at least that how I interpreted the OP.
 

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The Gen I would do this as well. Yesterday for the first time I used my ICE due ERDTT, but instead I selected HOLD as soon my car started. I did that knowing the ERDTT was going to run but with an 11 mile trip the cycling would yield poor fuel mileage.
 

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I got out of work today and it was about six degrees Fahrenheit. I started my car and the motor came on instantly. I knew that would happen. What surprised me is that while I was waiting for the heater to warm up I had an idea. I hit the gas pedal, honestly not expecting a damn thing, but to my surprise the motor reved up more. Not like a normal ICE car but it did rev up higher. I was able to make it rev up enough to start putting electricity back into the battery. I didn't know you could do this. So for any of you who didn't know now ya do.
Yup. GM put this in to make it seem more "normal", and it was discussed in a few thread years ago, but they might not have come to the attention of newer people.

On generation one, it'd go up to 1700 rpm from the normal 1400 rpm - right to the base of the peak efficiency range. I haven't seen any reports from an instrumented generation 2 car about the rev ranges, but I'm not surprised the firmware includes the response.
 

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I'm wondering about this whole discussion. I don't think the "gas pedal" does anything in neutral or park. Revving the ICE was probably just your imagination.
It's quite real, at least on first generation cars. There's no physical connection between the throttle body and the pedal, of course - but to make the car seem more natural, GM coded it so if the engine is on in Park (and maybe Neutral? I never tested that,) the engine does rev up a little when you push the pedal.
 

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It's to assist with service testing.
In a regular ICE car you can do that while parked to check idle vs load and different speeds.
With the way the engine runs in volt (off when stopped, not connected to pedal position), you really can't.
So this lets you do the same kind of test in a volt as you would in any other car when there are engine issues that need testing (low rev vs higher rev)

You can also do it during EMM to make it finish faster if you've arrived at your destination and it's not complete yet (if you don't finish it, it will just start all over again on next drive - so better to put the pedal down and wait)
 

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I'm wondering about this whole discussion. I don't think the "gas pedal" does anything in neutral or park. Revving the ICE was probably just your imagination.
No, I did this the other day too. What you describe is true when the engine is off, but not when it is on.

I got to work and just as I was pulling in, the temp went to 14F and my engine turned on (thanks ERDTT). Since I was seconds from a parking spot, I let the engine run a bit for its own health, rather than a quick on off sequence. I pressed the accelerator, and the engine idling increased a bit, noticeably so. It's also not the first time I've done this.
 

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Using the ICE to charge the battery is very inefficient and will cost more in fuel consumption cost than the same amount grid charged.

There are a couple videos that demonstrate Mountain mode charging from a depleted battery SOC up to the MM limit with the vehicle parked. Call it generator mode. As I recall the ICE burned Over Half a gallon to get 15 miles of EV range.


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