lack of power from stop so annoying

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electronchaser

Well-known member
Joined
Nov 8, 2019
Messages
80
So I have an i3 2019 and a 2018 330e. Been driving the i3 on longer treks, using the 330e mostly for city runs, visiting family etc.
So I've gotten very used to the incredible amount of passing power in the i3. I also have noticed that its power is very retarded when starting from a stopped position.
What doesn't make sense is the 330e has a weaker 84hp 190ish torque, electric motor, but when I put it in max edrive and mash the pedal it just jumps off the line with unreal urgency. this only lasts until about 25mph, and then its much more gradual. but it is explosive, whereas in the i3 it is very much subdued, and incredibly bothersome.

I was never able to punch this car from a standstill during numerous test drives due to traffic conditions, and was only able to really squeeze it while in motion. I think had I experienced this retardation in initial power, it would have been a deal breaker for me. I think BMW did a real disservice to drivers and the overall public in giving the perception of an EV taking off from the line like a Sentra.

Having driven a model 3, and the 330e for over a year (put 16k miles on her, 11.5k of them pure EV) ,
even test driving a Leaf with the bigger pack and motor, which had horrible torque steer.

I assumed, all EVs have that initial burst. I'm a sucker for that.
BMW got so much right....this item...they really messed up.


The fact that I'm out here putting bad press regarding this issue, shame, I'd much rather be singing praise and just off the walls happy after getting the 'ultimate driving machine' .

I hope BMW scouts read this,: bring back the power, I'll prepay you guys for all the mounts I'll end up breaking, but please let me and others enjoy the car for the 3 years I signed up for. Really. (At least up it just a tad, and get rid of that dead spot. ) Thx :)
 
My 2019 i3S Rex also takes off like a rocket from stand still. I mean, it actually presses you back into the seat :) It is "almost" Tesla like :)
 
WHat mode are you running your car in? That can make a difference in how power is applied.

If you can look at the traction indicator, does it appear to be flashing when you're trying to accelerate at a high rate? If so, the computer is restricting power because it seems to be sensing tire slip. If that isn't actually happening, the sensor(s) might be defective.
 
jadnashuanh said:
WHat mode are you running your car in? That can make a difference in how power is applied.

If you can look at the traction indicator, does it appear to be flashing when you're trying to accelerate at a high rate? If so, the computer is restricting power because it seems to be sensing tire slip. If that isn't actually happening, the sensor(s) might be defective.

just plain old comfort mode. The 330e snaps my head back from 0-25, very tesla like surge of instant pulling power. the i3 not at all. I'll try to get a few friends/fam to help shoot a video of both cars taking off side by side.
* I'm very fair minded, I wouldn't 'amp' up my disappointment if it wasn't so apparent in the fun factor dept.
for example, I do love the 25-50mph power surge the i3 has. Always puts a smile inside and outside :)

Never had the traction nanny flash me other than during a turn there was a bump that upset the car's balance. In fact, given the anemic take off power, it would be the last indicator I'd ever imagine seeing. Seriously.
 
Here is a video of an i3 beating an M3 off the line - the M3 doesn't gain on the i3 until they hit 60.

https://insideevs.com/news/319271/video-bmw-i3-versus-bmw-m3-0-to-60-mph/

And one of an i3 beating a Golf Polo GTI Turbo off the line

https://www.youtube.com/watch?v=Iyk8p4fh6mw


,,, and against a Mini Cooper S - beats it off the line
https://www.youtube.com/watch?v=Ml3mDa23Hgk
 
Yeah, something isn't right there. In Comfort mode my 2014 i3/Rex is VERY quick off the line. I'd like to put it up against my wife's 535i xDrive sometime, but she's not a racer so haven't been able to talk her into it yet. The 535 is quick but I think the i3 would take it until at least 30-40 mph.
 
MKH said:
Here is a video of an i3 beating an M3 off the line - the M3 doesn't gain on the i3 until they hit 60.

https://insideevs.com/news/319271/video-bmw-i3-versus-bmw-m3-0-to-60-mph/

And one of an i3 beating a Golf Polo GTI Turbo off the line

https://www.youtube.com/watch?v=Iyk8p4fh6mw


,,, and against a Mini Cooper S - beats it off the line
https://www.youtube.com/watch?v=Ml3mDa23Hgk

These videos are exactly what I fell for as well. But if you pay attention to the date of these videos (except the i3s video) , they're all 5 year+ old videos.
The bmw sales reps gave me the same line about it being the quickest BMW off the line, even vs the M cars etc. If the claim was even half true, I'd probably be one of the happiest i3 owners to date.

This is exactly where I think BMW did the disservice to drivers, because my 120ah BEV doesn't even come close to launching like those in the video do. I think they definitely detuned or retuned the power curve.

(This part is HUGE) Again going back to an apples vs apples comparison, my 330e weights 4000lbs, driving it in electric only mode, it should be murdered by the lighter, and more powerful i3 electric drivetrain. But the total opposite is true. (this is only true from a standstill until about 30 mph max).

Fisher99 said:
Yeah, something isn't right there. In Comfort mode my 2014 i3/Rex is VERY quick off the line. I'd like to put it up against my wife's 535i xDrive sometime, but she's not a racer so haven't been able to talk her into it yet. The 535 is quick but I think the i3 would take it until at least 30-40 mph.
I really really wish I could say the same. From my 6 weeks with the car, I have tried numerous red light drag races with random cars and drivers, most recent embarrassment was getting left in the dust by a friends newer nissan altima. He was already a car a half ahead of me before I felt the i3 move into the power band area, and the g forces started pressing me back. I wouldn't even waste the electrons trying to launch against an AWD 535i in my i3. :)

It's a pleasant day with ideal weather, let me see if I can get that video done and uploaded....

Thanks for the input and personal driver feedback. I've only recently transitioned from BMWs performance and M branded cars to the more green and eco models. The 330e impressed me big time, it had the nearly the same launch performance with its tiny little electric motor as my much more powerful 340i did.
 
MKH said:
Here is a video of an i3 beating an M3 off the line - the M3 doesn't gain on the i3 until they hit 60.

Funny, I'm going to soon drive the i3 bev to Dallas from L.A., just waiting for a few more electrify america stations to go live so I'll be able to map everything out more efficiently, time wise. (at present I'm at approx 31hrs TT with 8 hours total charging 23 hrs driving.) With a few more stations, I'll be able to drive faster, and spend more time charging (mostly a wash eta wise).

I did test drive an i3s rex, but I had 500lbs of humans in the car plus me. So that plus the weight of REx setup really didn't give a proper test drive either. I was willing to get a i3S bev just for the wheel /tire upgrade, well worth it to me, but none existed spec'd the way I wanted, and i missed order cutoff by a few weeks.

Plus sales guy literally said, you'll only feel the difference in the top end say from 60-90. And I do less of those, and way more 0-45 pulls.

I've been trying for weeks to get over it, enjoy other aspects, but nowadays, with a certain project I'm working at, I do so much stop and go driving daily, and its so irritating every single time to be let down when you know that the power is there (I mean I'm certain the i3 can accelerate with the same punch and surge of power from 0 mph, as it does when you mash the throttle at 25-40mph). But, its not.

I'm so close to loving this car, sounds weird, even to me. So close. This weekend I've thrown this car around turns that it shouldn't be able to handle, but it does, with grace. most definitely have pushed it to limits, and beyond, its amazing how good it is. On good asphalt, hot day, 33psi fronts, 36psi rears, on factory 19 all seasons, everyone I've taken on the twistys with me has been really impressed. It doesn't scare you on the turns, which to me is classic bmw.

Just that initial burst. Its too underwhelming (again relative to what an animal the i3 can be at 30mph if you squeeze the accel pedal).

Can the motor control module be reprog, /flashed/hacked in any manner ? Where would one begin?
 
These curves came from GPS recorded data on our 2014 BMW i3-REx:
GPS_010.jpg

  • GPS samples every second so low end accuracy is limited.
  • Can re-run tests with high resolution accelerometer data IF someone else has any.
There are multiple smartphone apps that can record GPS and acceleration data. Use yours and share the data here.

Bob Wilson
 
bwilson4web said:
These curves came from GPS recorded data on our 2014 BMW i3-REx:
GPS_010.jpg

  • GPS samples every second so low end accuracy is limited.
  • Can re-run tests with high resolution accelerometer data IF someone else has any.
There are multiple smartphone apps that can record GPS and acceleration data. Use yours and share the data here.

Bob Wilson


Thanks for sharing your exp and data Bob. But I can see it even from the data log you posted ( don't know if it has to do with low end accuracy with GPS) , on all 4 runs, it took about 2 seconds to reach 10mph, and from there onward the next 2 second interval you're at 30, and 2 seconds after that you're at 50.

on a side note: I know your REx is a bit heavier, but how much do you benefit from having the older, smaller pack, vs me with the 120ah. I recall reading something like the 120ah versions have 8 x 55lbs modules?
 
I thought it odd that on the various i3 boards, with numerous owners on their 2nd and 3rd i3 lease, not one was reporting any acceleration 'lag' with their 2019 i3 compared to their earlier ones.

Guy at work has a 330e, and I asked him to test drive my i3 for his opinion. He just laughed and said he didn't need to, had test driven i3's, and said you are right, there is a difference in acceleration off the line between the i3 and the 330e - but that it was an Apples and Oranges comparison - not 'electric' to 'electric'. He said when you floor the 330e, you get the electric instant torque acceleration, plus the gas engine kicks in temporarily, like a booster rocket, for additional acceleration until you get up to speed (your zero to 25 mph 'unreal urgency' is gas-engine powered). He said it is seamless, and you almost don't notice it, but it happens, so you don't get the 'smooth' electric car acceleration, you get a hybrid electric start and acceleration plus a low-end gas engine kick in the pants on top of that in the 330e, which just doesn't exist in the i3.

You are comparing acceleration between an all electric car, and an electric car with gas engine-assisted take-off. So it's not so much that the i3 has an acceleration lag, but that the 330e has an acceleration boost.
 
Yeah, I still think there's something that's not right about your i3. You mention having to wait for it to get into the power band, but with the i3's electric motor you have full torque immediately. No waiting to get into a power band. My i3 accelerates just like the ones in the videos that were posted.

The only vehicle I've actually raced was my son-in-law in his brand new Honda CR-V turbo. We only raced to 60 mph, but I left him so far behind that it was actually embarrassing.
 
I believe that the 330e's electric motor is in the automatic transmission which shifts up through the gears in electric mode thus multiplying its electric motor's torque when in lower gears such as when starting from a stop. This is an advantage over the i3 with its single-speed transmission.

Also, the i3's electric motor mount has been a weak point that has cost BMW a lot of money when the motor mount bolt or the mount itself has broken. BMW redesigned the weak motor mount starting with the 2016 model which made it less likely to break. Also, the traction control software was modified to prevent a rear wheel from spinning up rapidly when it is briefly loses contact with the road (when dropping down over a curb, for example) and then drops to the road. BMW might also have reduced the initial torque when starting from a stop to protect the motor mount.

The 120 Ah battery pack is only 40 kg heavier than the 60 Ah battery pack. However, some features that were options on 2014 North American i3's are standard on 2019 North American i3's (e.g., DC fast charging, backup camera, seat and battery pack heaters) which adds some weight to the 2019 model.
 
MKH said:
I thought it odd that on the various i3 boards, with numerous owners on their 2nd and 3rd i3 lease, not one was reporting any acceleration 'lag' with their 2019 i3 compared to their earlier ones.

Guy at work has a 330e, and I asked him to test drive my i3 for his opinion. He just laughed and said he didn't need to, had test driven i3's, and said you are right, there is a difference in acceleration off the line between the i3 and the 330e - but that it was an Apples and Oranges comparison - not 'electric' to 'electric'. He said when you floor the 330e, you get the electric instant torque acceleration, plus the gas engine kicks in temporarily, like a booster rocket, for additional acceleration until you get up to speed (your zero to 25 mph 'unreal urgency' is gas-engine powered). He said it is seamless, and you almost don't notice it, but it happens, so you don't get the 'smooth' electric car acceleration, you get a hybrid electric start and acceleration plus a low-end gas engine kick in the pants on top of that in the 330e, which just doesn't exist in the i3.

You are comparing acceleration between an all electric car, and an electric car with gas engine-assisted take-off. So it's not so much that the i3 has an acceleration lag, but that the 330e has an acceleration boost.

No, no gas power! :)

Hehehehe, its okay, I guess you didn't read some of my posts. LOL I've put 16K miles on the 330e, with a physical tach 20 inches from my eyeballs, I think I can tell when the car is in hybrid mode vs all elec mode.
It is apples to apples because I'm comparing the 330e in max e-drive. which locks you into to electric only powertrain, not hybrid. Its only when squeeze the pedal past the kick down sensor (little click in the gas pedal), until that point there's nothing but electrons pushing you down the road.

If I were to compare the i3 with the 330e in full hybrid mode, it would be painful.
(Have you seen my raving praise of other aspects of the i3? Just this one item that kills the joy factor. For me. )

So my complaint still stands, and my comparisons are spot on, (owning both, and knowing how to operate them).


alohart said:
I believe that the 330e's electric motor is in the automatic transmission which shifts up through the gears in electric mode thus multiplying its electric motor's torque when in lower gears such as when starting from a stop. This is an advantage over the i3 with its single-speed transmission.

<span>Also, the i3's electric motor mount has been a weak point that has cost BMW a lot of money when the motor mount<a href="http://www.mychevybolt.com/forum" class="interlinkr" target="_blank"> Bolt <span class="tip">Visit the Chevy Bolt EV</span></a>or the mount itself has broken. BMW redesigned the weak motor mount starting with the 2016 model which made it less likely to break. Also, the traction control software was modified to prevent a rear wheel from spinning up rapidly when it is briefly loses contact with the road (when dropping down over a curb, for example) and then drops to the road. BMW might also have reduced the initial torque when starting from a stop to protect the motor mount.</span>

The 120 Ah battery pack is only 40 kg heavier than the 60 Ah battery pack. However, some features that were options on 2014 North American i3's are standard on 2019 North American i3's (e.g., DC fast charging, backup camera, seat and battery pack heaters) which adds some weight to the 2019 model.

You have a really good point. Yes I was aware that the tiny little motor was housed in the transmission, but didn't consider the gearing aspect playing a big role in accel. Its only suppose to be a 84hp electric unit, but feels more than twice as powerful. I'll have to study this point further.
And the 330e in electric only mode doesn't give you access to 1st gear. (to get first gear , you'll need to either tap the 'minus' wheel mounted shifter, or slide the tranny into D/S mode, but that also fires up the petrol engine).

That's amazing if they were able to double capacity on the packs with just a 40kg increase in weight. Wow!

And it does suck that the engineers didn't bother upgrading the engine mounts and instead detuned power from the motor.
 
Fisher99 said:
Yeah, I still think there's something that's not right about your i3. You mention having to wait for it to get into the power band, but with the i3's electric motor you have full torque immediately. No waiting to get into a power band. My i3 accelerates just like the ones in the videos that were posted.

The only vehicle I've actually raced was my son-in-law in his brand new Honda CR-V turbo. We only raced to 60 mph, but I left him so far behind that it was actually embarrassing.

I do too !
I mean to give the most minimalist breakdown:

full throttle:
0-25mph feels like a sentra
25mph+ amazingly, fun car, with joy-inducing acceleration.

I feel the instant torque the moment my foot's 1/4 inch into the pedal, but the car doesn't surge forward. I can only describe it as a semi-decent rolling start. not a launch. The motor seems to boog down and then gradually starts pulling.
BUT......When you mash the pedal at 25, its just a sling shot effect. So why doesn't this sling shot exist from a stop?

Try it, go 25mph, mash the pedal, feel how brutally quick it is?
now try it from 0mph.
 
electronchaser said:
And it does suck that the engineers didn't bother upgrading the engine mounts and instead detuned power from the motor.
The original polymer (reinforced nylon?) mount was replaced by an aluminum mount that accommodates a larger, stronger motor mount bolt, so BMW engineers did redesign the mount. However, BMW did not authorize replacing the polymer mount with the improved aluminum mount on 2014-2015 i3's instead adjusting software to reduce the stress on the motor mount which is shameful.

I don't believe that we know for certain that the motor's torque was reduced. Full torque was probably never available at 0 RPM because traction control would reduce torque when the inevitable loss of traction is detected.
 
BMW did not authorize replacing the polymer mount with the improved aluminum mount on 2014-2015 i3's instead adjusting software to reduce the stress on the motor mount which is shameful.

They also replaced the existing bolt with a stronger bolt. When, as 2nd owner, I went in to the Dealership for the scheduled brake flush on my 2015, I asked about the 'recall' and if it had been done to my i3, since I could see that it still had the plastic mounts. The Service Adviser pulled up the service records and showed me the work order, which listed both bolt replacement, and software update. He said BMW would not authorize the actual mount replacement unless it was failing (cracked/leaking oil/broken).
 
And it does suck that the engineers didn't bother upgrading the engine mounts and instead detuned power from the motor.

Yes - but would the 'detune' still be present in a 2019 with the aluminum motor mounts? That would be worth knowing.
 
Something seems off with your i3s. Mine is super quick off the line in Sport mode.

I had a Chevy Volt which was very, very quick to 30 mph. Were it RWD it'd smoke a lot of cars to even 60 mph.

I would have it reflashed or checked out.
 
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