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Discussion Starter #1
I know I should probably stop complaining about little things and be grateful that I haven't had any more battery segment failures, but I must know if I'm not the only one noticing this.

Sometimes it seems like the transmission gets a little misaligned after stopping, and right when I start to accelerate, the car jerks back a little after accelerating for a second, like it "slips". Feels a bit like an automatic shifting gears, but it happens in EV-only mode and it's at about 1-2 MPH.

Last night it happened right as the ICE was starting (C/S mode), and it was so exaggerated I thought I ran over something for a second. The only way I can describe it is it felt like I was accelerating, abruptly took my foot off the pedal, and then mashed it back on the pedal right away (but of course I didn't...my foot was firm on the pedal the whole time).
 

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Sometimes it seems like the transmission gets a little misaligned after stopping, and right when I start to accelerate, the car jerks back a little after accelerating for a second, like it "slips". Feels a bit like an automatic shifting gears, but it happens in EV-only mode and it's at about 1-2 MPH.
I've also noticed this recently at very low speed and only occasionally when creeping in traffic, and thinking back it seems (but not 100% sure) like it started after I got the 2 software updates (#16055 and #27660) done in December.
 

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I always thought this was the auto-hold feature when going up an incline. The system auto-breaks ("holds") the Volt while you swap foot from brake to accelerator pedal.

I'll have to double check my Volt's settings but I think I have this set, and yes, I do notice a slight hesitation in both EV and ICE modes. I thought it always happened when on a slight incline, but it's so brief that I don't find it annoying. I'll have to confirm tomorrow.
 

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+1 I have this too, doesn't happen all the time, but when it does, it's noticeable, is it annoying? No. It seems that there's clutch activity between MG1 and MG2.
 

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Discussion Starter #5
I always thought this was the auto-hold feature when going up an incline. The system auto-breaks ("holds") the Volt while you swap foot from brake to accelerator pedal.

I'll have to double check my Volt's settings but I think I have this set, and yes, I do notice a slight hesitation in both EV and ICE modes. I thought it always happened when on a slight incline, but it's so brief that I don't find it annoying. I'll have to confirm tomorrow.
I only notice it on flat ground.

I know the auto-hold feature you're talking about, though; I have it at the "5 minute" setting. I actually just noticed for the first time the other day that it displays a message on the DIC indicating that "Hill Start Assist Now Active".

+1 I have this too, doesn't happen all the time, but when it does, it's noticeable, is it annoying? No. It seems that there's clutch activity between MG1 and MG2.
Yeah...it's not really annoying, but it can be surprising (especially, apparently, when it happens as the ICE is starting...I thought I lost power for a split second). You're probably right about the clutch activity. I notice that if I try and feather my brakes as I stop (nearly completely releasing them before the brake 'jerk back') it tends to happen more. May be something to do with transitioning between braking and accelerating at low speeds.
 

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Hmmm, don't notice anything on flat ground and definitely don't see the brake assist message on the DIC (I keep eye on leaf and ear out for backfire on incline accelerations from full stop). I must not be experiencing what everyone else is experiencing.

Guess I only have this slight hesitation when my foot moves from brake to accelerator. I must be juuuust fast enough that the Volt starts to fall before I start to accelerate.
 

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Taking my 2017 back to dealer tomorrow to see if they can "undo" the "16055" update. I went from owning an electric smooth car to one that surges and clunks. Glad I can tell them it's not just me!
 

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I have a similar issue when I'm in hold mode, stopped at a light and the engine is still running.

The feeling I get is like the car is bucking just a little bit even when I have the brakes applied, it's not like its trying to hit the car in front of me, but just a whole car kind of jerkiness from the car wanting to send the power generated *somewhere* or as if the clutches controlling where the power is set to the wheel is still engaged. It disappears as soon as the car realizes it's at a stoplight and shuts off the engine.
 

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Discussion Starter #9
I have a similar issue when I'm in hold mode, stopped at a light and the engine is still running.

The feeling I get is like the car is bucking just a little bit even when I have the brakes applied, it's not like its trying to hit the car in front of me, but just a whole car kind of jerkiness from the car wanting to send the power generated *somewhere* or as if the clutches controlling where the power is set to the wheel is still engaged. It disappears as soon as the car realizes it's at a stoplight and shuts off the engine.
I would get that before my plugs were replaced...when it was cold and the engine was warming up, it would run so roughly I suppose the extra vibration threw off the clutch or something. I do notice a bit of "shifting around" or jerking when the engine stops or starts at a stoplight.
 

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I have a similar issue when I'm in hold mode, stopped at a light and the engine is still running.

The feeling I get is like the car is bucking just a little bit even when I have the brakes applied, it's not like its trying to hit the car in front of me, but just a whole car kind of jerkiness from the car wanting to send the power generated *somewhere* or as if the clutches controlling where the power is set to the wheel is still engaged. It disappears as soon as the car realizes it's at a stoplight and shuts off the engine.
. I found this only happens if you stop very gently and hold the brake softly. You can make it stop by pressing once firm on the brake pedal (after you feel the surge) then you can continue holding the brake softly and it won’t surge anymore
 

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Could very well be a plug misfire

Plugs not burning off carbon or maybe even moisture in the cylinders ( if you aren’t on ICE a lot ) .....??
 
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