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I was on highway for a few miles this weekend and used the gas engine for it (by switching to the hold mode).

The highway has some uphills (but not very steep like mountain inclines). I can hear the engine revving but I am not so used to the revving sound I am hearing from the volt.

What I am used to for an ICE engine (from traditional gas engine cars that I've owned), the revving sound correlates directly to how much I am pressing on the gas pedal. The revving sound gets louder as I press the gas pedal more, etc.

On 2018 volt, the revving sound doesn't correlate at all. Sometimes, I can hear the loud revving sound (as if I am flooring the gas pedal, although I am not. I am not on cruise control either as I wanted to test this.) Then it goes away and back to quieter low-rev sound.

I read gen 1 folks experience this kinda of behavior. Is this something gen 2 owners are experiencing as well? I am feeling this disconnect between the gas pedal and engine response, and it feels really strange.
 

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In hold mode the engine runs as needed to maintain battery charge level within a range around the point when hold was activated. There is no direct relation to pedal position.

Sounds like normal behavior.
 

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I was on highway for a few miles this weekend and used the gas engine for it (by switching to the hold mode).

The highway has some uphills (but not very steep like mountain inclines). I can hear the engine revving but I am not so used to the revving sound I am hearing from the volt.

What I am used to for an ICE engine (from traditional gas engine cars that I've owned), the revving sound correlates directly to how much I am pressing on the gas pedal. The revving sound gets louder as I press the gas pedal more, etc.

On 2018 volt, the revving sound doesn't correlate at all. Sometimes, I can hear the loud revving sound (as if I am flooring the gas pedal, although I am not. I am not on cruise control either as I wanted to test this.) Then it goes away and back to quieter low-rev sound.

I read gen 1 folks experience this kinda of behavior. Is this something gen 2 owners are experiencing as well? I am feeling this disconnect between the gas pedal and engine response, and it feels really strange.
The accelerator pedal (not the gas pedal) activates the electric motor to control the speed of your car. The gas engine is used as a generator to maintain the state of charge when in hold mode. These 2 things do not always equate to each other.
 

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Possibly the oddest thing a new Volt owner has to get used to. The car will pull from battery first to respond like an EV. Then once the ICE has revved up the battery draw will be reduced and depending on the situation the car will run the engine at either a higher RPM or for longer than needed for direct propulsion, giving it a chance to recharge the batteries back to the charge sustainment point. In any case my 2017 is nowhere near as loud as a traditional car.
 

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Here are your operating modes.

Gen2 is a bit different than gen1, but you can still get the engine revving differently than what you expect at times. Both are technically eCVTs (electronic CVT) where the motors can make the ICE rpm vary significantly at a fixed vehicle speed, depending on many factors. Took me a while to get used to on gen1, but it doesn't bother me now. You'll get used to it ;) rest assured the car is figuring out what is most efficient for those conditions and that is why it is doing what it's doing.
 
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What I am used to for an ICE engine (from traditional gas engine cars that I've owned), the revving sound correlates directly to how much I am pressing on the gas pedal. The revving sound gets louder as I press the gas pedal more, etc.
That's how traditional ICE's operate - You're correct. On a Gen 2 Volt, there is no connection at all between the 'gas' pedal and the engine. You press the pedal down and the computer decides what it needs to do to meet your request - That may mean speeding up the ICE a bit . . . . or not. Even in the Hold mode, there is no direct correlation between the speed of the car and the speed of the engine

Don
 

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There is not usually a direct correlation. But there is some correlation. If you set the CC or ACC (to get your foot out of the equation) you'll find that the engine whines pretty loudly as you hit an incline. On a flat surface, you will find the engine speed goes up and down as necessary to keep the car going, and maintain the battery charge to where it was when you went to Hold mode.
 
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There is not usually a direct correlation. But there is some correlation.
The ICE can connect directly with the wheels via one planetary gearset, but the car can still speed up and/or slow down while the engine maintains a constant RPM selected by the computer. It can do this because the electric motor is also connected directly to the wheels via a second planetary gearset and the computer can speed up or slow down the car by varying the speed of the electric motor alone, if needed. The speed of the car is a combination of the speed of both the ICE and the electric motor. To slow the car down, the electric motor can even run in reverse if needed, if the speed of the ICE is needed to be kept high for power generation purposes

Don
 
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In other words the position of the accelerator pedal tells the computer what you want to do and the computer tells the two electric motors and ICE engine what to do depending what mode it is in (Normal, Sport, Mountain or Hold) and depending how GM programed the computer to get most efficient drive from those modes.
 

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You'll eventually learn the patterns of the ICE in the Gen 2. Coming from the Gen 1, the Gen 2 is MUCH more connected to the go pedal than the Gen 1, but it's still not linear. There are also 3 distinct "extended range" modes (for on ICE). Each has their own ICE behavior. Here's a rough summary so you know what to expect.

Low-speed, extended range mode -- operates much like a serial hybrid, usually less than 40 MPH but more reliably "serial" at lower speeds. ICE will shut off for periods of time for battery power only and then starts back up to "recharge." This is VERY common especially at less than 25 MPH when it seems the Volt's goal is to keep the engine off as much as possible. This was a common complaint in Gen 1 when owners would end up at stop lights with the engine blasting. It can still happen in the Gen 2, but less so.

The Fixed Ratio and High Extended Range Modes are a little more complex, but here's what I've observed since I use the ICE the most at higher speeds--

when ICE is engaged:

first 30 seconds -- idling for warmup, little response pedal engagement
2-5 minutes -- after a quick "whirr" to connect, runs at low RPM, still drawing significantly from battery in a power-split mode, will draw from battery more than ICE if needed. I feel like it's still letting the ICE run at a lower RPM to have it warm up some more before hitting the high RPMs.
5 minutes or more -- ICE maintains direct connection, little battery assist (at high-speed highway driving).
If going up hills, will draw from battery and then will try to "recharge" but usually "holds off" until you get to 63 MPH or less, which means you may notice MORE engine noise at 63 MPH than 75 MPH because the Volt was waiting for a lower speed to rebuild the battery buffer.

Hopefully you won't ever learn these details because you won't use the ICE enough. Unfortunately, I do.
 

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You'll eventually learn the patterns of the ICE in the Gen 2. Coming from the Gen 1, the Gen 2 is MUCH more connected to the go pedal than the Gen 1, but it's still not linear. There are also 3 distinct "extended range" modes (for on ICE). Each has their own ICE behavior. Here's a rough summary so you know what to expect.

Low-speed, extended range mode -- operates much like a serial hybrid, usually less than 40 MPH but more reliably "serial" at lower speeds. ICE will shut off for periods of time for battery power only and then starts back up to "recharge." This is VERY common especially at less than 25 MPH when it seems the Volt's goal is to keep the engine off as much as possible. This was a common complaint in Gen 1 when owners would end up at stop lights with the engine blasting. It can still happen in the Gen 2, but less so.

The Fixed Ratio and High Extended Range Modes are a little more complex, but here's what I've observed since I use the ICE the most at higher speeds--

when ICE is engaged:

first 30 seconds -- idling for warmup, little response pedal engagement
2-5 minutes -- after a quick "whirr" to connect, runs at low RPM, still drawing significantly from battery in a power-split mode, will draw from battery more than ICE if needed. I feel like it's still letting the ICE run at a lower RPM to have it warm up some more before hitting the high RPMs.
5 minutes or more -- ICE maintains direct connection, little battery assist (at high-speed highway driving).
If going up hills, will draw from battery and then will try to "recharge" but usually "holds off" until you get to 63 MPH or less, which means you may notice MORE engine noise at 63 MPH than 75 MPH because the Volt was waiting for a lower speed to rebuild the battery buffer.

Hopefully you won't ever learn these details because you won't use the ICE enough. Unfortunately, I do.
I've discovered that if I keep my KW usage below 19 the ICE won't turn on for up to a half-mile of steady low speed driving.

The last observation on this about the ICE not recharging the battery above 63 MPH would help explain what I saw driving across Kansas last year in Mountain Mode. ICE turned on between Kiowa and I-70 but when I hit Topeka where I got off I-70 I had zero miles of EV range left. My Volt, despite being in Mountain Mode the entire way, had used all the battery and not replenished it.
 

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We have a 2016 Volt Premier with 40,000 miles and 13,000 miles just on the gas engine. I have noticed that while in hold mode with a 90% charged battery the engine will shut off for some time while driving at low speed 40 MPH or so. Than when the gas engine kicks in I noticed by using the trip meter the mpg (on the gas engine) will read 24 mpg or so at 40 MPH or so, than you can hear the gas engine seem to relax, sometimes you can hardly hear it, and the MPG will increase to well over 50 MPG. Also you can see on the dash when the engine is just supplying energy for propulsion and when its supply energy to the battery and propulsion as well.

Its all done by computer even if you have it in cruise control the engine rpm's will fluctuate. Still a pretty fuel efficient method of gas engine operation GM has designed the Gen 2 Volt. Our last trip yesterday for 61 miles on gas only was over 58 mpg, and 67.6 miles on electric and still had 3 miles left when we arrived home.

Our 2014 Volt at best would get low to maybe mid 40's mpg on gas, and 45 miles on a full electric charge in summer driving...
 

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Its all done by computer even if you have it in cruise control the engine rpm's will fluctuate. Still a pretty fuel efficient method of gas engine operation GM has designed the Gen 2 Volt. Our last trip yesterday for 61 miles on gas only was over 58 mpg, and 67.6 miles on electric and still had 3 miles left when we arrived home.
And this is a tangible demonstration of how hold-mode can waste gasoline. Maybe that could have been 58 miles on gas only if it had just been left to run down, instead of burning that extra 0.06 gallons...
 

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This is the way most hybrids operate. Volt does it with more battery range, so, the driver would notice more fluctuations in the ICE operation. There is very little sync between the go pedal and the gas engine. It's all computer-controlled drive-by-wire stuff.
 

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And this is a tangible demonstration of how hold-mode can waste gasoline. Maybe that could have been 58 miles on gas only if it had just been left to run down, instead of burning that extra 0.06 gallons...
Interestingly, it reads in hundredths of gallons, but only updates in 3 hundredths of gallons (e.g. .01, .04, .07, etc.).
 

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I got locked out (somehow I couldn't log into my account, I swear I am using the correct password, anyway, recreated my account, same email, same username. Thought it would error, but it didn't.)

Anyway, thanks for the response and insights guys. I guess I need to get used to this disconnection feel between the engine response and the go pedal (my bad it is not the gas pedal anymore, at least not all the time). We are doing a road trip (5 hrs+) this weekend. I guess I will have some more quality time with the car and learn how things work again.
 

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The way the car works is pretty complex. Although there are some definitive-sounding answers here, I've seen others elsewhere (such as car magazines) that explain it slightly differently. My experience with hold mode has been that in general, at highway (Interstate) speeds, with a decent charge on the battery and the battery not trying to catch up to the hold point, the engine is direct-coupled to the drive wheels and it drives much like a normal gas car if you are cruising. If you step on the gas hard, the battery kicks in to assist. After that, the engine may rev higher than your pedal position indicates so the charge can get back to your "hold" point. At lower speeds the computer is really doing its thing and it is pretty hard to predict exactly what the engine will do and when. As stated elsewhere here, there are general tendencies (like engine off at a light, using the battery in lower speeds, etc.). If you take a long trip on the interstate in "hold" you'll probably see modest engine activity and almost no battery activity. The times the battery/electric kicks in to assist seem to be recharged when you are coasting downhill or slowing down a little in normal driving.
 

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The disconnect seems really odd at first, but eventually you get used to it and realize that is the way a car really should work. Then ICE cars seem to operate strangely.
 
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