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Discussion Starter #1
While climbing a 7% grade for about 5 miles, the ICE became very loud but I was afraid to accelerate above 50mph as the car seemed to be excessively straining. I did not observe the rpm. I did set to mountain mode well before the mountains and had about a 15 mile EV reserve during the climb. On milder grades, I noticed it rev'd to ~3000 RPM and was able to maintain 55-60mph, beyond that, I felt I'd be over straining the ICE. Is this normal? I was somewhat disappointed with the lack of power.

It appeared that regen'd EV range would force the car to go into EV mode while I was in hold or mountain mode and the EV miles were added to the gas miles. ie: If I descended a long hill, the EV range would increase by 10 miles and even though I was in hold mode the car would use battery only at times and add the miles to gas miles. I switched to hold mode rather than mountain because I felt I needed more reserve than MM provided.

I got 47mpg (US gallon) over the 500 mile trip which was pretty good considering most of the trip was in the mountains, but that was including the regen'd miles which does tend to skew the mpg.

Coolant temp maxed at 104C on long climbs but averaged 65C - Is this an issue?
 

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How heavily loaded was the Volt? Were you towing a trailer? The engine coolant temperature would not be a problem unless it reached ~ 115C - 120C (240F - 250F), the Volt would let you know if the engine was overheating. As with any ICE, if you were concerned the engine was overheating you could turn off the AC and turn up the cabin temperature control so that some of the excess heat produced by the engine dissipates through the cabin heat exchanger.
 

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Everything you described is normal behavior. The coolant temp was perfect for running the ICE. I actually find the Volt does really well in the mountains. The immediate torque makes climbing a breeze unlike my SUV which struggles mightily going up the same roads.

As for RPMs, I assume you are using some ODBC tool/gauges on the car to monitor this as AFAIK the Volt does not have a RPM display.
 

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Discussion Starter #4
No trailer, no AC, just one light passenger and maybe 70lbs of luggage. It was really struggling on that 7% grade and pressing down the accelerator had little effect. Energy flow showed "Engine and battery power"

I used Mygreenvolt to see the engine RPM
 

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While climbing a 7% grade for about 5 miles, ... I was afraid to accelerate above 50mph as the car seemed to be excessively straining. ...had about a 15 mile EV reserve during the climb. ....and was able to maintain 55-60mph, beyond that, I felt I'd be over straining the ICE. Is this normal? ....
These were just your feelings.
With that EV reserve you had Full Power on tap. All you had to do was step on it and ignore 'What the ICE "felt" like'.
Did you know you have a Cruise Control at no extra cost?:)

I hope you didn't become a road obstacle driving that slow. (Think; the Prius reputation...)

Until the EV buffer is used up, which you were far from, this car is as fast at 14,000 ft. elevation as it is at Sea Level.
You can't say that about many cars.
The car will pop up a display when the EV buffer is gone, and only then will you be running on just ICE power.

Try listening to music or an interesting podcast! Turn it up!
 

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The Volt engine sounds like it's straining even going up mild grades, much less 7%. Despite that there is plenty of power. Forget about the sound, just floor and go. It will climb easily.
 

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I think you've gotten used to not having the engine run at all so any sound from the engine will sound like straining. Small displacement 4 cylinder engines always sound like they're straining when running at higher RPMs, even when using engine braking while descending mountain passes.
 

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One of the strangest things to me about driving a Volt is that the engine RPM is not directly affected by the accelerator pedal position. When the engine revs up high, it makes me want to let off on the pedal, but you have to develop different driving instincts in a Volt. Ignore the engine revs (within reason).
 

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While climbing a 7% grade for about 5 miles, the ICE became very loud but I was afraid to accelerate above 50mph as the car seemed to be excessively straining. I did not observe the rpm. I did set to mountain mode well before the mountains and had about a 15 mile EV reserve during the climb. On milder grades, I noticed it rev'd to ~3000 RPM and was able to maintain 55-60mph, beyond that, I felt I'd be over straining the ICE. Is this normal? I was somewhat disappointed with the lack of power.
It's fine. That's how this car works. "Full power" will scream up to about 4200 RPM and it'll do that even after the demands are done for a while, but it's DESIGNED to do that. That's how you get power out of a little, efficient engine. *Extra* power comes out of the battery. Mountain Mode gives more margin of available extra the car will allow you to tap. It will TELL YOU when you don't have any more extra by putting up a message that says "Propulsion Power Reduced". If you've been screaming up hills, that says "well, gotta slow down for a while". If you haven't, it means "the main battery detected a potential problem. Go report this to the dealer."

It appeared that regen'd EV range would force the car to go into EV mode while I was in hold or mountain mode and the EV miles were added to the gas miles. ie: If I descended a long hill, the EV range would increase by 10 miles and even though I was in hold mode the car would use battery only at times and add the miles to gas miles. I switched to hold mode rather than mountain because I felt I needed more reserve than MM provided.

I got 47mpg (US gallon) over the 500 mile trip which was pretty good considering most of the trip was in the mountains, but that was including the regen'd miles which does tend to skew the mpg.
All completely normal. There's basically two points of charge that the Volt is keeping the battery between when it's "run out" and the ICE is coming on: a low and a high. The low one is the point at which the ICE actually comes on, and if it dips more below that low, the engine runs harder to catch up. If the amount of power drifts over the high point (which is a couple hundred watt-hours above the low), then then ICE shuts off. This often happens on downslopes, but CAN happen just at moderate speeds driving along on the flats -- the lowest engine operating speed is about 1400 RPM and that's often generating more power than is needed to cruise along at 70-80kph. It slowly builds up excess charge until it hits the high point, then the ICE shuts off until you use up that little buffer and drop to the low point again. All that gets recorded as gas miles because it took burning gas to get to that circumstance; the top of the hill, the top of the charge buffer, either one. Only the earliest Volts (2011 and 2012) can be fooled into thinking those are electric miles and they'll just punish your MPG in trade, so you can't game both of them on the same trip.

Coolant temp maxed at 104C on long climbs but averaged 65C - Is this an issue?
Nope. That's completely normal. Mixed dexcool's boiling point is about 109C and the system is designed to take a bit of pressure too, which further raises the boiling point. A couple above 100 is just "yeah, baby, clicking along great!"
 

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I've taken my Volt over the Lincoln Gap in Vermont without any problems, the Lincoln Gap is the steepest grade in North America, 25 degrees. Going over mountains is where the Volt really shines, regen braking makes going downhill a pleasure because you have so much more control then when you are using friction brakes. I didn't need friction brakes on either the Lincoln Gap or on Mount Washington, just put it in L and used the regen paddles when needed. The Volt will recapture a lot of energy going down a steep mountain road, I got over 5KW back on by descent from Mount Washington.
 

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While it may seem to be under powered, that's just the EV elastic band effect. I never had a problem in normal traffic, never even tried the Sport mode yet. Going up the Malahat a few months ago in Mountain Mode I was following an SUV that was passing a truck. After the pass he didn't pull over into the right hand lane so I pulled over to the right hand lane and passed him quite quickly without flooring the accelerator. Surprised even myself. It all happened without a lot of hallabilou that you get with an ICE engine. Yes the ICE was turning at a steady higher rpm to put out some electrons but a completely different experience. If I didn't have the passing of the SUV that had passed the truck I would have no idea. Normally going up this hill I have to pick up speed/rpm to maintain speed in fifth on the TR7 or to keep from downshifting in the Integra.
 

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It sounds normal to me too, even though I have yet to tackle much of a grade in our Volt yet. Not too many mountains in Minnesota.

I think much of this is about perception. Back in 2002, I drove my '01 Miata through the Rockies in Colorado. The sound of the engine at higher rpm's was music to my ears. I can't imagine ever feeling that way about the ICE in our Volt.

Sent from my SM-G930V using Tapatalk
 

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While it may seem to be under powered, that's just the EV elastic band effect......
I think the 'Elastic Band Effect' is a Prius thing, and maybe other Hybrids.
You step down, and wait,, while the engine picks up RPM and the ECVT finds the ratio that keeps the power as high as possible,,, (not that much), There is never a surge of power.

With the Volt Max Power is always a step away. (unless you managed to drain the Hybrid buffer in the pack by not using MM when needed.)
You step down and "You Go Now" !!!
 

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Discussion Starter #14
Oh yeah, on steep descents, love the regen and complete elimination of friction brakes. I wish there was variable regen available as L sometimes slows down too much and D not enough so I use the paddle with D which is somewhat jerky.

I never did floor it, maybe pushed the pedal 1/2 way and pushing to 2/3 hardly changed the acceleration, That engine noise just didn't sound good.

bjrosen: How did you know that you recaptured 5KWH? The energy display only shows KWH used.
 

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I think the 'Elastic Band Effect' is a Prius thing, and maybe other Hybrids.
You step down, and wait,, while the engine picks up RPM and the ECVT finds the ratio that keeps the power as high as possible,,, (not that much), There is never a surge of power.

With the Volt Max Power is always a step away. (unless you managed to drain the Hybrid buffer in the pack by not using MM when needed.)
You step down and "You Go Now" !!!
The pick up is gradual unless you really step on it. It is programed that way to maximize the battery (the greater the acceleration, the more battery is used). That's why there is a sport mode. You don't get something for nothing. Basic law of physics.
 

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... I wish there was variable regen available ....
There is such a thing!!!
It's called driving in D and using the brake pedal to slow at the rate you want to, just like a normal person.
No shifting or herky jerky paddle pressing required. :rolleyes:
And no friction brakes until you max out the regen.

here we go again.....
 

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I use the paddle with D which is somewhat jerky.
As you practice with it, you will get smooth with it. Smooth paddle driving requires adding gas and brake at the right times to take over outside of the paddles limits.


I never did floor it, maybe pushed the pedal 1/2 way and pushing to 2/3 hardly changed the acceleration, That engine noise just didn't sound good.
The problem with the car is that it partially relies on the pre-conditioned lump of grey matter we carry with us and position behind the steering wheel...

The car's computer knows better what needs to be done than we do. When you want to go faster, just put the gas pedal down! Remember - the pedal isn't directly connected to the engine - the car will figure it out.

The Volt is different from normal cars in other respects, also. To save weight, there is less/different insulation in the cabin so the noise may sound relatively unnerving compared to other modern/heavy cars and the Volt's engine is engineered specifically for higher RPM's. It spends most of its time driving a generator whereas a regular car's engine moves a driveline - so it's a completely different type of power train and is optimized for a different type of operation.
 

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KW used goes down when you recapture energy, I recorded the KW used at the bottom of the mountain. at the top and then the bottom again. At the top of Mt Washington I had used 10.6KW, at the bottom after the descent it was 5.7KW sp I recaptured almost 5KW.
 

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Oh yeah, on steep descents, love the regen and complete elimination of friction brakes. I wish there was variable regen available as L sometimes slows down too much and D not enough so I use the paddle with D which is somewhat jerky.

I never did floor it, maybe pushed the pedal 1/2 way and pushing to 2/3 hardly changed the acceleration, That engine noise just didn't sound good.

bjrosen: How did you know that you recaptured 5KWH? The energy display only shows KWH used.
Use cruise control with L and the car will maintain the same speed all the way down except for the very steepest grades.
 

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Discussion Starter #20
There is such a thing!!!
It's called driving in D and using the brake pedal to slow at the rate you want to, just like a normal person.
No shifting or herky jerky paddle pressing required. :rolleyes:
And no friction brakes until you max out the regen.

here we go again.....
I tried this tonight and it works well, except I have no idea when the friction brakes actually engage. Mygreenvolt has a setting to produce an audible alert when they are engaged but I never hear it.
 
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