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Discussion Starter #1
I guess I'll post this in general because I'm not convinced it is a "problem"...

Today I asked my 3 teen kids how they liked the Volt compared to the Challenger SRT that I traded and my boy says, "drift into the driveway and I'll give it respect". :) So I figured just after I turned into my driveway I'd stab the throttle to at least give them a little scratch. I stabbed the throttle to the floor and released it immediately and it did exactly what I wanted: tires screeched and it lunged forward BUT: it continued to accelerate for about a half second after my foot was completely off the accelerator which also resulted in a longer screech than I was expecting.

Is this a known "phenomenon" in the Volt? I was thinking maybe the motor controller takes a half second to disengage or that maybe it doesn't cut power instantly to prevent shock on the drivetrain? The end result is basically a non-issue I guess: I was just used to ICE being more instant on the release. It was strange feeling the accelerator pedal in the full up position but the car still accelerating hard for about a half second. Also seems strange that the power came ON immediately as soon as I stabbed it but took a half second to "roll OFF".

Thanks,
Mike
 

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Which mode were you in? Was the gas engine on or off?
 

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Try it in LOW...although if your traction control is active, it will disengage regen and only allow friction braking for the ABS system to activate.

So if you usually drive it in LOW, but the screeching tires activated the traction control cutting off regen, it might have given you the impression that the car continued to lurch when it was really that you expected regen and it didn't happen. Letting off the go pedal in "D" also has a bit of regen, but I'm not sure if the same lack of regen in D would give the same impression.

I'm not sure if turning T/C on or off makes any difference. Also, what year is your Volt?
 

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Discussion Starter #4
It's a 2017 LT. I had it in D and was in Normal driving mode. It was definitely still accelerating after I released my foot. Here's a ~1 second clip of the event. When you watch (listen to) this, keep in mind that I stabbed and released the accelerator from 0-100%-0 as quickly as I could. If you do that motion with your foot while sitting at your computer, you'll realize that the tire squeal continued beyond when you lifted your foot: that was the sensation I got when driving it. Meaning that I still heard squealing for I'd say 1/4 to 1/2 second after my foot was completely off the accelerator:

https://youtu.be/RAS1v94dCdE

Mike
 

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It kind of makes sense. With a standard ICE, the pedal is tied directly to a throttle which has direct correlation with how high the engine revs. It's not the same with an EV. I believe the EV pedal triggers some electronic mechanism that spins up the electric motor. It stands to reason that if you quickly stab/release the pedal, it may keep the motor engaged for a half-second to spin up/down.

Also - keep in mind that unless you were in sport mode, the pedal response is ever so slightly delayed.
 

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I've never driven a Gen 1, but I know my Gen 2 has a bit of roll-in/roll-out. If I don't mash the accelerator, it sort of "fades in" the acceleration, and if I do, it's pretty much instant, but releasing the pedal (no matter how fast) still has a little bit of "fade out" before it returns to full coasting. It doesn't feel like it's sticking; it just feels like it has a bit of springyness in the acceleration. The total time to return to coasting is about a half second.
 

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I remember when my mom put our '68 Impala 4 barrel through the garage door. I guess it didn't release quickly enough either ;)

Today almost all throttles are computer rather than cable controlled. What you describe doesn't surprise me at all. And it certainly doesn't concern me since no one actually has any need to drive like that.
 

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Discussion Starter #11
I remember when my mom put our '68 Impala 4 barrel through the garage door. I guess it didn't release quickly enough either ;)

Today almost all throttles are computer rather than cable controlled. What you describe doesn't surprise me at all. And it certainly doesn't concern me since no one actually has any need to drive like that.
Yeah, probably a good idea to put the garage door up first. Give yourself that extra 21 feet. :D Like I said, just establishing a norm, not calling it a problem. If it had stuck for maybe 8 seconds and I ran out of 120 feet of driveway, another 200 feet of open field, and then hit the woodline, I'd complain.

If that's the boy's attitude, I'm not so sure he should be driving.
He's not. He's 14. Have to teach them how to do a proper burnout early. :p

Mike
 

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He's not. He's 14. Have to teach them how to do a proper burnout early. :p
My kids are even younger, and I have to be so careful now that they pay more attention. My son now loves it when I'm in a hurry and zip around a corner. And my daughter has already admonished me for driving with alacrity. I want them to understand very clearly that these things are NOT ok.
 

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Discussion Starter #13
My kids are even younger, and I have to be so careful now that they pay more attention. My son now loves it when I'm in a hurry and zip around a corner. And my daughter has already admonished me for driving with alacrity. I want them to understand very clearly that these things are NOT ok.
Having taught one to drive and facing teaching my youngest in about 6 months, the thing I found most helpful was to impress upon them that driving is life or death. Once they grasp the concept that lack of attention or ignoring safety due to ANY distraction could lead to DEATH, the rest of your guidance to them sinks in a bit better. The key is to get them to understand the seriousness of driving without making them scared to drive... but they do reflect on what you've told them so that just before they do that stupid thing they know they shouldn't be doing, they think back to what dad said and wonder "could this be the last thing I ever do?" Then they make the right decision.

Mike
 

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Well my one-year old 2017 Volt just did that on the Highway at 50 km/hr and it kept accelerating after I took my foot off the pedal. I braked, the car slowed down; I took my foot off the brake without touching the accelerator pedal and it started to accelerate again. Went through that cycle twice and finally I reached down and pulled the accelerator pedal up and that cured it. Scary. Just to check, I repeated the exercise and it is repeatable. Car was driving in default Normal mode with gas engine running because of the temperature (-13C); car had driven about 2km after fully charging the battery and sitting in the garage overnight. In the good old days, I would have concluded that the throttle linkage was stuck/frozen, but that isn't supposed to happen anymore. As I recall, Toyota had an similar "issue" a few years ago. Oh yes, there is no problem with the accelerator pedal interacting with the carpet. I checked. Moral: don't floor your Volt.
 

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Discussion Starter #15
That sounds like a different problem than what I had. In my case, I could feel (with my foot) that the pedal had returned to the up position but acceleration continued a good fraction of a second after the pedal had returned to the up position.

FWIW I've put 2000 miles on it since that time and it has never happened again. Then again, I have not stabbed the throttle and released it immediately since then either: there's just no reason to do that in a normal driving scenario. So it's possible that the "speed controller" for the motor just isn't programmed to react that quickly.

Mike
 
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