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Discussion Starter #1
I have had my 2012 Volt a little over 2 months. I absolutely adore it, but it is doing something that gives me cause for concern.

I have noticed that it occasionally seems to hesitate or lose power for a few seconds when it should be accelerating. It seems to happen most often early in a drive, usually when I am running on battery power. I press the accelerator, but the car doesn't accelerate. Instead, my speed drops, and there is a 1-3 second hesitation before it "catches" and becomes responsive to the accelerator again. Needless to say, it is a little scary when this happens, especially when attempting to merge into traffic. My significant other was in the car with me Friday and it happened twice. I thought he was going to go into orbit, since obviously this is a good way to get run over. (Pressing the gas harder doesn't have any effect, by the way.)

Has anyone else had this issue, or does anyone have an idea as to what causes this and what the remedy might be? The dealership says there are no software upgrades for my car, and they are going to have a service tech drive it after lunch to try to duplicate the issue.
 

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I would immediately take it to a service dealer. If the problem persists it could get worse than better over time...so either way I would want to kow what is causing and get it corrected real soon !
 

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Discussion Starter #3
I typed the original post from the customer lounge of the dealership's service department. I just wanted to throw the question out there for ideas in case they can't make it do it when the service tech drives it.
 

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This sounds like the transition when the smaller motor (and/or gas engine) is unclutched from the planetary gears. That's a normal condition that should feel similar to a conventional automatic transmission when you suddenly floor the accelerator and the transmission "steps down" a gear to enable ultimately faster acceleration. There is a brief pause in the power. It shouldn't last longer than a second or so while it switches the transmission over to using only the big electric motor. If you press the accelerator less aggressively you may get better overall acceleration response.
 

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Speed dropping and several seconds isn't normal. If you're over 50 mph or so, the car shifts into two motor EV for efficiency after 20 or 30 seconds without accelerating - and the shift back feels like a fast transmission kickdown - a short hesitation/slow acceleration followed by a surge. There's no way it should take several seconds or have you slowing down, though - that sounds like a car problem. (and it won't happen below 50 - you didn't give us a speed.)
 

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Discussion Starter #6
You are correct; I didn't give you a speed. Sorry about that. It's usually at pretty low speeds. I'd say less than 30-35 mph.
 

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You are correct; I didn't give you a speed. Sorry about that. It's usually at pretty low speeds. I'd say less than 30-35 mph.
30-35, and all electric, not extended range? That's definitely not normal.

(You can get something sorta similar to what you described in normal operation at 35 or above with the engine on - if you manage to catch the car halfway through the series-power split transition and hammer the throttle. It's the only time the car feels off balance in my experience.)
 

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(You can get something sorta similar to what you described in normal operation at 35 or above with the engine on - if you manage to catch the car halfway through the series-power split transition and hammer the throttle. It's the only time the car feels off balance in my experience.)
Yeah, that happens to me occasionally, but the ICE has to be running. The dip in power is disconcerting compared to how the Volt normally operates (smooth accelerations), but it is no worse than the average shift in a traditional manual transmission. It might be a bit worse than a twin-clutch/DSG transmission, but not seconds worth of lag.
 

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@Jenn, my MY 12 does the same thing. I mentioned this to my salesperson and he acknowledged that he was 'aware' of the condition and 'shrugged his shoulders' as in "That's normal." When you want to get going 'in-a-hurry' I've found that it is usually best to go 'soft' on the accelerator pedal to start and then 'ramp-it-up.' In my mind, it has to be some sort of programming 'thing'. I'd like to hear from our Volt Rep on this...
 

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Discussion Starter #11
@Ladogaboy, this is actually worse and more prolonged than the shift of a traditional transmission. It almost feels like it has shifted briefly into neutral, where pressing the accelerator is completely useless.

@RCB268, the owner of the dealership where I bought it also drives a Volt, but says he's never had this issue. The last I heard, they were charging the battery. They said it needed to be on electric for part of the testing. I've been here for 3.5 hours now. I suspect they are going to tell me there is nothing wrong with it, at which point my significant other will come unglued. He is convinced it's going to get me killed.
 

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Jenn ... As 'the man' said: I hear you!" PLAN AHEAD BEFORE ACCELERATING! Sometimes... And, I mean 'sometimes' and not all the time. Usually, my Volt exhibits 'throttle-lag' when I am on the xway doing 70ish and want to 'scoot-over-there-right-now' and it doesn't happen. "Hello, Engine Room. Is anyone there?" Since we seem to be in the minority when it comes to owners suffering this 'affliction'... at least you and I could use 'some answers.'
 

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@Ladogaboy, this is actually worse and more prolonged than the shift of a traditional transmission. It almost feels like it has shifted briefly into neutral, where pressing the accelerator is completely useless.
As others have said, that is definitely not normal behavior. I hope they can get this diagnosed and fixed for you.
 

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The last I heard, they were charging the battery. They said it needed to be on electric for part of the testing. I've been here for 3.5 hours now.
They should start it up in mountain mode and let it charge the battery with 15-17 miles of range using the gas engine. That is several times faster than charging at 240V. Starting from an empty battery, it shouldn't take more than 15-20 minutes or so.
I suspect they are going to tell me there is nothing wrong with it, at which point my significant other will come unglued. He is convinced it's going to get me killed.
If they don't figure it out and you do drive it again, take along a notebook so the next time it happens you can immediately write down the conditions under which it happened -- speed, battery level, whether the gas engine was already running when you accelerated, how hard you accelerated (did you 'floor' it?).

You may need careful records to sort this out and without immediately writing it down eyewitness observations can be surprisingly inaccurate.
 

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No way this is normal. One of the great things about the Volt is that there is never hesitation. A salesperson who says otherwise just doesn't know the car.

I will say that I usually drive in Sport. If I forget and drive in Normal I fell that there is a hesitation. LOL

Keep us posted.
 

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It isn't going into a low traction event, is it? Sometimes it's hard to see, especially if it happens quickly, but next time it has this hesitation, check the DIC and see if it says low traction. Perhaps a wheel speed sensor is momentarily dropping out.
 

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Thanks, chevytechnician! Will do.
 

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It isn't going into a low traction event, is it? Sometimes it's hard to see, especially if it happens quickly, but next time it has this hesitation, check the DIC and see if it says low traction. Perhaps a wheel speed sensor is momentarily dropping out.
Oh, that's a good thought. If she's hitting ice, and the traction control is knocking back the power in response, that could be kinda similar (though it shouldn't be slowing down from that - just not accelerating.) The TCS light (little yellow car with curvy tracks behind it) flashes for a few seconds after regaining traction as well as during the event.

Or if a defective wheel sensor is somehow fooling it (but I thought they were fail-safe in that it knows the difference between a failed/disconnected sensor and a spinning/stopped wheel.)
 
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NEVER EVER, NOT EVER, NEVER!

Jen-

Having driven over 13,000 Miles since new, March, 2012, I can state that I have never experienced what you are describing.

As a major proponent, owner and salesman of this amazing machine I have been compelled to "Demonstrate The Products "Capabilities", over these past eleven plus months and by this I mean- Exhilerating Performance Demonstration on city streets and local freeways.

(Note- In My Own Machine, Not The Dealer Volt Fleet- Obeying The Push Speed Limit Locally -For The Most Part- LOL)

The challengers, have been left in the dust. The tight gripping 100% torque in Sport Mode/"L" is masterful and quick, very quick, sure footed!

Performance car street racers jaws drop, stunned by being bested by a Chevy Volt!

And Now they want to know more about it-

Seriously, in the over 31 Volts that I have driven, I never have experienced what you describe.

As you have described it, if accurate, is NOT NORMAL and the cause should be determined with proper study and corrected.

Remember, you must drive the Volt with the Tech, ride with the tech, show the tech what you are doing as the concern happens.

I am confident that this will happen for you as many Chevrolet Chevy Volt Techs have spent hours on end in class, on webnars and hands on, deep diving into the amazing technology of The Amazing Chevy Volt EREV.


All will be well and soon you will be shouting that old song- With apologies to- Johnny Paycheck and David Allan Coe

"Take This Gas And Shove It,
Ain't Buying Much No More-
Cruzing In My Chevy Volt-
With The Pedal To The Floor,

Driving By Them - Fillen Stations,
Pluggen In At Home,
Unplug A Lamp, Plug In My Volt,
For Bout A Buck A Day!

Take Your Gas And Shove It,
Not Buying Much No More,
Crusing In My Chevy Volt,
Who Could Ask for more.................................................."

Best-

Thomas J. Thias
 

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Discussion Starter #20
They were unable to duplicate the issue I described at the dealership yesterday, but they did install a software update, the nature of which the service technician was unsure. He asked that if the unspecified update did not fix the problem, that I take very detailed notes as to when it does it (battery level, speed, temperature, etc.) in the hope that they can replicate it. It was 36* this morning, and there were no issues. Granted, it doesn't happen every morning, so I am not turning cartwheels yet, but I am hopeful.

I had my tires rotated while I was there yesterday (I'm at 7500 miles; I drive A LOT), and of course, they aired them up. I checked and my air pressure is higher than I have had it previously. I was thinking about that in terms of the traction control possibility that ChevyTechnician and Saghost discussed above. Generally the conditions have been dry, and I do not recall having seen the traction control light come on, BUT in keeping with the same idea, could/would low tire pressure have been the culprit?
 
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