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When accelerating{flooring her} from 44 to 59 mph our Volt falls on it's face, about half the time!
The first time I demonstrated this, late last year the Technician explained it; as the lag when it switched from EV to ICE(HE DID EXPLAIN IT IN SIMPLER TERMS, THOUGH)! I know the Prius: like our last car, may work this way; not my Volt! He also told me"GM was 1 year behind in letting him get a training class", and Certified! He had gotten Toyota hybrid training, however. Never even hooked it up to the Computer, I drove the exact Volt in their lot and it did not have this delay and Salesman could verified! I asked the Service Writer to let their mechanic drive it??? This suggestion fell upon DEAF EARS: I suppose??
Earlier this year again, Another Dealer; it was explained away as being normal. That Dealer successfully did 2 software updates, so I'm finally getting better EV and mpg's! Huh, too bad their updates were 4 years late in coming.
Wednesday it was again explained away by yet another Dealer(we have no Chev dealer closer than an hour) as; the battery getting low and the lag is "in determining when the Battery gets near low and making up for it by starting the gas engine". They kept it overnight, to charge the battery and find the same hesitation. They did absolutely nothing to it!
It does it in L, D Sport, Normal, EV and Ice approximately 40% of the time!
Is your Volt a Dogg, too? I'm afraid of getting run over it is that extreme when pulling out sometimes.
Even from 0 mph last Saturday, when pulling out from a stop under the highway in a 35 or 45 mph zone and a semi was coming barreling up on us and it lagged terribly!
 

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Gen 1 standard operation. When you're cruising at a constant speed above 35mph in CD mode (battery), only MGA (the low power motor) is running the car. When you floor it to pass, the clutches have to switch to MGB and spin up. There is a noticeable lag. Not 2-4 seconds, but sure 1 long second or so. It's the way it works. Has nothing to do with the gas engine. If you're really seeing a 4 second delay, that sounds like a problem.

If you're accelerating from a lower speed (less than 30mph), MGB is running the car, and no lag on flooring it. From a complete stop, yeah sometimes feels like it should be quicker, but no complaints here.

Gen 2 changed this by having two more equal electric motors that are both running at the same time. No Lag. Now it's still only 149HP total. So at highway speed, you can't expect V8 like passing power.
 

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The Volt has 2 electric motors and there are times when it must clutch the planetary gears in and out depending on required torque. Just as when shifting a manual gearbox you have to let off the power momentarily.

There's one section of the Coquihalla Highway where my Volt will consistantly "stumble" for a moment (about 10-15 seconds after passing through the snowshed at 77 MPH) Now I totally expect it as it's just the Volt doing it's thing.

http://gm-volt.com/2012/02/24/watching-the-volts-4et50-transmission-shift-gears-in-extended-range-mode/
 

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Step 1. Get a paper bag.
Step 2. Breath into it.

The drama and hyperbole and exclamation points and all caps are unneeded.

Let's get some facts. Go out to someplace with no traffic with a passenger and a stop watch. From a standing stop, floor the car in Normal, Drive and record the seconds it takes to get to 30 MPH, 45, 40, 45, 50 and 60 MPH. Report back.
 

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"It does it in L, D Sport, Normal, EV and Ice approximately 40% of the time! "

Just curious, can you get the symptoms to appear when running in Mountain or Hold modes?
 

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Since you state this is reproducible (about 40% of the time), then record these events with your phone in real time and report your finding to the dealer and this board. This will help clear things up quickly.
 

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My 2012 doesn't seem to do anything like this. Or at least as it's presented here. It's really peppy and responsive at any speed. And while it's hard to determine what the OP is really saying, if it's anything like what he/she describes it sounds like something's not working right.
 

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When you feel like crap isn't working right 2 seconds seems like 4 or more. I have done a good 2 Mississippi count several times after coming up behind somebody doing 45 to 50 mph and following them for a while before I get an opportunity to pass. The "clutch, spinup, engage" cycle seems to take forever even when you know what is going on and are expecting it. I have gotten into the habit of hitting the accelerator as oncoming traffic is about to pass the car I am going to pass... by the time the oncoming traffic passes me the Volt has done its "hokey pokey" routine and is ready to accelerate.

Keith
 

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I think post #2 has it the wrong way around.

So if you have been driving 'nicely' above 35mph or so for more than a few moments, both MGA and MGB will be running. This is so that both, together, each run at a slower speed, but combined can deliver the number of revolutions/min required for that speed.

For reasons I guess are related to the rated performance of various components, the Volt/Ampera will not allow you to use the combined power of both MGA and MGB. I would presume it is because as there is no one-way clutch, if the torque output of MGB exceeds some value (it is the more torquey motor) then it will push MGA backwards. The only way the two can operate together is when their torque outputs are similar.

So when you demand high power whilst in 'CD2' (both motor outputs added together) it has to quickly drop into CD1 (MGB only) to deliver max torque. How quickly is a function of the clutches and software. I guess it will be slightly different for different cars.

SOLUTION:- If you don't like this, or it happens more than you expect, use 'SPORT' mode, which keeps the car in CD1 mode a bit longer than CD2. It will (= should!) still happen, it is designed to drop into CD2 for efficiency, but SPORT tends to hold CD1 longer and will make that transition early if it anticipates you're about to stab the pedal.

Likewise, if you can see ahead you are going to need a sudden burst of power, like for an overtake, give the pedal a quick stab a little earlier and it will drop into CD1 in anticipation of more large-displacement pedal demands.

NOTE - I am making some inferences here about what the car does in SPORT because I don't know for engineering certainty, but that's how it appears to behave to me.
 

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Sad part about this situation is that the dealer is correct that this is normal.... but the dealer has no idea how the car works and is making crap up to explain why it is normal.

Keith
 

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Before gen2 was released, we had a lot of discussion on MGA vs MGB modes, I'd really like to review this again now that we should have all the facts. Maybe someone can list some specific posts? They're hard to find, given all the pre-production speculation. Also very curious how the ELR 2014/2016/Bolt would react in the same situations. ELR may have the same issue? About 2 months ago, I was really looking to upgrade to either a gen 2 or an ELR. Then, like the OP, I had two similar instances, where the lag caught me by surprise when trying to pass. I'm not asking for "sports car" performance, but I am asking for Predictable performance.

I previously had two cars with turbos, both with significant turbo lag. They were actually a lot of fun. The lag was predictable, there was a boost gauge, you learned how to drive it. But apparently I'm still learning with Volt after 2 years of driving.
 

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It's no different than any automatic car cruising in overdrive gear.
If you floor it, it will take a second to kick down and really get going.
There have been several other threads on this before.

I guarantee you it is not 4 seconds. 4 seconds is an eternity when you are driving.
If you actually record it you will find it's less than a second.

The simple way to avoid this altogether is to give the pedal a little surge prior to your real acceleration to let it shift down. Then feel free to floor it a second or two later for real. Or just hold the pedal down, it does the same job.
Or accelerate more moderately instead of flooring it.

If you start from a stop, you will never experience this. It is by design, and it only happens when driving 60km/h or higher for a sustained length of time that it deems should go into two-motor mode for efficiency.
 

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I have never experienced this personally however I have never "floored it". There is rarely the need to "floor it" or brake hard. Doing so on a regular basis is bad driving. Practice smooth driving, safe following distances, and anticipate upcoming traffic flows. If you are accelerating like this on a fully depleted battery you will temporarily deplete the buffer affecting performance.
 

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So... being a Sunday morning, I decided to go for a Sunday morning drive, TX130 is 1 mile from my house. Fastest speed limit in the US. :) No, not to go fast, but tried to repro the issue of MBG lag, from flooring it at different speeds. Bottom line, I really couldn't. TX130 has feeder lanes, paralleling the main lanes, where there is little traffic. All CD1 or CD2, no ICE driving. I DID repro it once, where I probably noted about a 1 second delay from 42mph, but all other times and steady speeds, the delay seemed less than half a second, or the acceleration met my expectation.

As I've said before, I understand the MG2 lag is as designed, no surprise there. But is there a way to tell if the car is in 2 motor or MGB mode?
 

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As I've said before, I understand the MG2 lag is as designed, no surprise there. But is there a way to tell if the car is in 2 motor or MGB mode?
If you have OBD you can monitor the stats of each (e.g. power level) When not in use MGA should be 0kw/0rpm

You can also test it if you have a steady foot and maintain identical pressure on the pedal when you reach cruising speed.
Watching the kW display on the dash, you should see it drop slightly. It's usually pretty quick to engage if you're cruising along at freeway speed.
 

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I think post #2 has it the wrong way around.

.....SOLUTION:- If you don't like this, or it happens more than you expect, use 'SPORT' mode, which keeps the car in CD1 mode a bit longer than CD2. It will (= should!) still happen, it is designed to drop into CD2 for efficiency, but SPORT tends to hold CD1 longer and will make that transition early if it anticipates you're about to stab the pedal.
.....
nothing that I've read or experienced in the car agrees with this statement. All that "sport" mode does is remap the accelerator pedal to command more power at a lesser pedal push, it does not affect systems operation at all. If you think it does, you have been reading the facebook page too much-
 

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A side effect of sport could keep you out of 2-motor mode more often, though, if you don't have a steady foot and spike the pedal enough to trigger declutching (which would be like halfway down in normal mode, harder to do by accident)
But I've seen no evidence that it actively remains declutched longer in sport vs normal under the same circumstances
 

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A side effect of sport could keep you out of 2-motor mode more often, though, if you don't have a steady foot and spike the pedal enough to trigger declutching (which would be like halfway down in normal mode, harder to do by accident)
But I've seen no evidence that it actively remains declutched longer in sport vs normal under the same circumstances
That could be why it looks that way to me. I use very light pedal displacements, and rarely use sport. No idea what facebook is.
 

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Discussion Starter #20 (Edited)
Our Volt is "Unsafe at Any Speed"!

When the prius mechanic at Mark Porter Chevrolet drove the car he experienced it. He said GM was not offering the volt class for a year? I drove an exact car on their lot and it did not exhibit these lags! I asked the service writer to have the mechanic drive that one; then i left : never heard back anything. I guess my request was ignored! 2 other dealers spewed the same bull. Yes we do sometimes drive our Volt like a normal automobile. We also have to travel hours to get Authorized service and I'm fed up. I want the car fixed.
 
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