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Lately, if I accelerate quickly from 0 - 50 mph, there is a split second loss of torque during the acceleration. If I drive like a sane person, the hesitation never happens. It's really not a huge problem, but I wonder if it's the first symptom of a much larger problem. My Bolt is a '19 with 14,000 miles and has not had one problem before this. I love the car!
 

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Lately, if I accelerate quickly from 0 - 50 mph, there is a split second loss of torque during the acceleration. If I drive like a sane person, the hesitation never happens. It's really not a huge problem, but I wonder if it's the first symptom of a much larger problem. My Bolt is a '19 with 14,000 miles and has not had one problem before this. I love the car!
With or without the traction control on?
 

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Lately, if I accelerate quickly from 0 - 50 mph, there is a split second loss of torque during the acceleration. If I drive like a sane person, the hesitation never happens. It's really not a huge problem, but I wonder if it's the first symptom of a much larger problem. My Bolt is a '19 with 14,000 miles and has not had one problem before this. I love the car!
When does it occur during the run? The first split second on the pedal? At 35mph, 50mph? Does it do it every single time. Also, please define split second. Something almost measurable like a half a second, or almost imperceptible like .0005?
 

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Lately, if I accelerate quickly from 0 - 50 mph, there is a split second loss of torque during the acceleration.
This came to mind:
 

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My 2019 does that pretty regularly. It's the traction control kicking on/off/on/off. I've proven this to at least my own satisfaction by retesting on multiple occasions after turning TC off. I've never gotten the hesitation with TC off. Keep in mind that when this happens, I don't feel or hear ANY wheel spin while the car is pulling power (hesitating). But I think the TC kicks in before you can detect it. Also consider that if this seemed to start recently, are you still on the original tires? That could be normal too: tires get harder and lose traction as they age so if they have a bit less traction now that you've put some miles on the car, the TC might kick in and be more noticeable to you now than it used to be.

I actually drove in Sport mode exclusively after discovering this hesitation and the hesitation is still there but it seems that TC (and hence the hesitation) doesn't kick in as often in Sport mode. I couldn't swear to it though. Might just be placebo.

Edit: I forgot to mention that I find it odd when this hesitation occurs that the power output on the display still reads 155 to 160 kW the whole time. That is, I can floor it and I feel the hesitation after the power meter has already reached 155kW and when it hesitates I can watch the meter and it stays at 155kW. You'd think if TC was pulling power, the meter would fluctuate. I never did get an answer to that anomaly.

Mike
 

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I don't see how that's applicable. How can the car "hesitate" when it constantly has the same power output. I don't think it applies the brakes to pull power. Does it?
Too much power = wheel slippage = traction control. 160KW is way more power than you need for starting from a standstill. You should only need that much power at much higher speeds or on quite a steep uphill grade.
 

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2 things I could never do with my F-350 Diesel and all my EV's.... tires spin outs
haha
I would think it is too much power, kinda like the 93 mph cut off
 

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actually that is exactly how traction control works, it applies brakes to the wheel that is slipping to shift the power to the wheel with traction Traction Control Explained
Why would it do that when it can just as quickly and easily control the electric motor output (and without wearing out the brake pads)? I could see why it would use the brakes for stability control, but not necessarily traction control.

Mike
 

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Because the front two half-shafts are fed by a single motor, you have overrun clutches for difference in shaft speed, but no other way to stop wheel spin on a single wheel while providing torque to the other.
 

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Discussion Starter #13
It happens at about 45 mph with no wheel slip (dry pavement) and less than half a second and almost imperceptible loss of torque. I've never turned off the stabilization control and haven't tried sport mode yet. I've never noticed the car passing 150 Kw. I was most concerned that the car was having a problem that could turn into a bigger issue. You have convinced me this is not the case. Thanks.
 

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The TC can kick in with no hint (to you) of wheelspin and it can happen at well under 150+kW. It just depends on the surface. I can go full throttle and never spin on rough pavement (like tar and chip type rough blacktop) but on a smoother road, I can't.

Mike
 

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It happens at about 45 mph with no wheel slip (dry pavement) and less than half a second and almost imperceptible loss of torque.
The Bolt also uses the brake system to counter torque steer.
 

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Lately, if I accelerate quickly from 0 - 50 mph, there is a split second loss of torque during the acceleration.
If you're talking about what I think you're talking about, it has nothing to do with traction. Its just the nature of modern cars, they delay your power delivery. Delay meaning there may be time delay between your foot/pedal and the response, also meaning the power ramps in a maximum pace regardless of your foot position. Even gasoline cars do it. Some worse than others. Anybody who has driven a pre-throttlebywire car knows how direct a car CAN feel.
 

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If one wanted to test this.. one could go to a prepared surface such as a drag strip. No matter how well prepped the surface is.. no matter how sticky the pavement, your Bolt will NOT ramp in the power as fast as the surface can take it. Its a predictive type of thing, your car is thinking what the "normal surface" with average traction is and is giving you what it thinks you can use.

I have noticed that the ramp curve can change. I'm not sure what the algorithm is based on. Maybe the previous 2 days or 20 miles or something? Not sure what makes it change. It can also change based on SOC but that is a different topic.
 

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I noticed that, too. To some extent it is related to steering wheel angle and some other factors, besides speed and traction of course.

I will not loose traction, but I can feel TC anticipating grip loss, or maybe even a tiny wheel slip that is otherwise undetected - TC will slightly limit power.

As for the 45 mph power loss - I will test it myself today. I never noticed that.
I can say; however, Bolt is kid of weird when it comes to power delivery. It slowly builds it.
Not like my sweet 500e - it would hammer it the moment you push the pedal. You really had to fight with the steering wheel over the torque steer.
 
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I noticed that, too. To some extent it is related to steering wheel angle and some other factors, besides speed and traction of course.

I will not loose traction, but I can feel TC anticipating grip loss, or maybe even a tiny wheel slip that is otherwise undetected - TC will slightly limit power.

As for the 45 mph power loss - I will test it myself today. I never noticed that.
I can say; however, Bolt is kid of weird when it comes to power delivery. It slowly builds it.
Not like my sweet 500e - it would hammer it the moment you push the pedal. You really had to fight with the steering wheel over the torque steer.
You ain't seen nuthin' 'til you put the pedal to the floor from a stop with a 1997 PbA EV-1. The torque steer was horrifically fun. GM toned down available torque in the NiMH '99s. I broke four sets of motor mounts in three EV-1s over five years. Those things were a kick in the pants...in a straight line.
 

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So, I pushed it several times, at different rates and loads.
No noticeable power change.
I could feel some power fluctuations, but those were grip and torque limiter related (I bet there is some limiter via software as I could feel more acceleration after 35 mph).
Other than that - nothing. I was at about 70% SOC, so enough juice.
It was cold, though, about 5-7 C (40 - 45 F?).

So GregBrew, you are saying EV-1 was even funnier than raw 500e? I never drove Tesla, so I cannot compare, but 500e feels more powerful than Bolt. Sure, above 40 mph Bolt gives more oomph. But from dead stop - it will not even spin tires. I can get some chirp at 30 mph, but dead stop.
TC on or off, Sport on or off - almost same take off.
Boring....
 
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