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Discussion Starter #1
I've been researching the Niro in prep. to buy new or used. Just came across a thread in 2017 forum about a "stutter" or "jerk" some owners have experienced that service departments apparently have no solution for.
Has anyone with a new 2018 experienced this?

Thanks for your input from a newbie.

Robert B.
Snellville, GA
 

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I've been researching the Niro in prep. to buy new or used. Just came across a thread in 2017 forum about a "stutter" or "jerk" some owners have experienced that service departments apparently have no solution for.
Has anyone with a new 2018 experienced this?

Thanks for your input from a newbie.

Robert B.
Snellville, GA
The Niro uses a dual clutch transmission (DCT) which is an automated manual not an automatic with a torque converter. This is done to improve efficiency. Torque converters are very smooth but waste power. The Niro DCT combined with the electric motor is a marriage made in heaven. Motors can start with Max torque from zero rpm and thus no clutch slipping is needed to start moving. You can creep along all day in EV mode with no damage to the clutches.

There are times when this motor DCT combination can be felt, just like one can usually feel a manual transmission shift. I view it as a feature not a flaw. I like the feel. However, if you think you want a torque converter in your transmission, don't buy the Niro.
 

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The Niro uses a dual clutch transmission (DCT) which is an automated manual not an automatic with a torque converter. This is done to improve efficiency. Torque converters are very smooth but waste power. The Niro DCT combined with the electric motor is a marriage made in heaven. Motors can start with Max torque from zero rpm and thus no clutch slipping is needed to start moving. You can creep along all day in EV mode with no damage to the clutches.

There are times when this motor DCT combination can be felt, just like one can usually feel a manual transmission shift. I view it as a feature not a flaw. I like the feel. However, if you think you want a torque converter in your transmission, don't buy the Niro.
You might be interested to know a little more about the motor DCT capabilities.

Given

Motor torque 125 ft lb 0-2500 rpm
DCT 1st gear final ratio, ~16:1, 6th gear ratio ~2:1
60mph tire rpm, ~800

starting torque at the wheels, ~2000 lb, (0 to 30 mph pretty good)
70mph 6th gear, motor ~2000 rpm, 250 ft lb at the wheels (250/3500=.07, 7% grade)

EV mode performance, not Tesla like, but capable.
 

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There is no stutter. Rather there can be a pause trying to do a fast start after taking your foot of the brake until the motor engages (nothing to do with the DCT which is already in gear). Seems to be by design engineering wise and software controlled. Early models received a firmware update that alleviated this issue but did not eliminate it. I haven't experimented myself with this, but Sport mode sharpens the responsiveness, and may help reduce any pause. Another thing one could try is launch control, left foot on brake and right foot on accelerator.

I seldom care about a fast start and the only time it really applies (for me) is crossing a road with traffic at a stop sign, or turning with traffic from a stop. I've just adjusted to this quirk and floor the accelerator half a second before I would in other cars. No issues in motion. My major issue with this lag in electric motor "crawl" is adjusting an inch or two in my garage. That's jerky and imprecise! You cannot simply lighten up on the brake pedal like ordinary automatics to move a smidge because of the pause in crawl function.
 

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I spent some time researching this reported problem as that was the only negative for us buying car (2017 Niro Touring ). I decided to buy it. Pressure from my wife who was very unhappy with our 2015 Ford C-Max after the third time the (little battery which appears to boot the computer). Try to find any info about this battery which hides under a panel in front of the rear bumper. Really obscure. Wife very pointedly reminded me she did not want to be stuck at the supermarket with two Grandchildren strapped into car seats.

Could not create the stutter problem in three Niros on dealer lots. Bought the car. A few days later I was able to create a symptom like described by others. I stopped sliding my foot off the brake as I applied gas and the problem never occurred again.

I like the car. Would buy another one in a minute. Took delivery Sept 2017.
 

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There is no stutter. Rather there can be a pause trying to do a fast start after taking your foot of the brake until the motor engages (nothing to do with the DCT which is already in gear). Seems to be by design engineering wise and software controlled. Early models received a firmware update that alleviated this issue but did not eliminate it. I haven't experimented myself with this, but Sport mode sharpens the responsiveness, and may help reduce any pause. Another thing one could try is launch control, left foot on brake and right foot on accelerator.

I seldom care about a fast start and the only time it really applies (for me) is crossing a road with traffic at a stop sign, or turning with traffic from a stop. I've just adjusted to this quirk and floor the accelerator half a second before I would in other cars. No issues in motion. My major issue with this lag in electric motor "crawl" is adjusting an inch or two in my garage. That's jerky and imprecise! You cannot simply lighten up on the brake pedal like ordinary automatics to move a smidge because of the pause in crawl function.
Interesting. I wonder if there is a difference between HEV and PHEV. I don't see this lack of a smooth creep mode at all. If I take my foot off the brake while in drive mode, the car will move smoothly forward, even on a modest grade. I'm in EV mode and the gas engine is not running.

If your gas engine is running, the jerking is probably the DCT clutch trying to close fully rather than "slipping the clutch", which is what you would do (slip the clutch) with a manual transmission.
 

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I have the 2018 PHEV and I have not noticed any stuttering. It's possible that it's there, but I'm not the kind of driver who cares about those sorts of things, I'm all about high mpg, reliability, and cargo space, "performance" is not my thing.
 

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Interesting. I wonder if there is a difference between HEV and PHEV. I don't see this lack of a smooth creep mode at all. If I take my foot off the brake while in drive mode, the car will move smoothly forward, even on a modest grade. I'm in EV mode and the gas engine is not running.

If your gas engine is running, the jerking is probably the DCT clutch trying to close fully rather than "slipping the clutch", which is what you would do (slip the clutch) with a manual transmission.
I was able to duplicate a stutter/shudder.

I put the car into sport mode which turns on the gas engine. I drove about a mile in sport mode which, by the way, is quite sporty. As I was coming up the hill to the base of my sloped driveway, I eased off the gas and turned into my driveway and then gently pushed the gas peddle. The trans stuttered/shuddered for a fraction of second and then smoothly went up the driveway. Inside the garage, the car creeped forward smoothly (like EV mode).

So yes, I would say you can get stutter/shudder when the gas engine and DCT clutches are closing too quickly(not allowed to slip). If the motor is driving the DCT, I never see the effect.
 

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Discussion Starter #11
I'm curious, and I haven't figured out yet what is the advantage of having a PHEV? I drive 80 - 100 miles most work days, so having a 25 mile EV range would be of limited use to me. You charge the PHEV at home, but it still performs regenerative self charging, right?
Forgive me if I seem ignorant of this, I just haven't taken time to research it for myself!

Thanks for your reply,
RB
 

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So yes, I would say you can get stutter/shudder when the gas engine and DCT clutches are closing too quickly(not allowed to slip). If the motor is driving the DCT, I never see the effect.
Wrong clutch. Your description is that of the hydraulic engine clutch which obviously has nothing to do with EV only mode.
 

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I'm curious, and I haven't figured out yet what is the advantage of having a PHEV? I drive 80 - 100 miles most work days, so having a 25 mile EV range would be of limited use to me.
Well, think about it. You would be in EV for 25 to 30% of all miles. Smart use limits EV to stop and go or low speed driving when your gas engine is at its lowest efficiency. Most PHEV owners report mpg in the 70's and 80's versus 40's and 50's in the HEV. This only gets better if you can recharge at work. Of course, you would have to factor in electricity costs.
 

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I'm curious, and I haven't figured out yet what is the advantage of having a PHEV? I drive 80 - 100 miles most work days, so having a 25 mile EV range would be of limited use to me. You charge the PHEV at home, but it still performs regenerative self charging, right?
Forgive me if I seem ignorant of this, I just haven't taken time to research it for myself!

Thanks for your reply,
RB
yes, 25/100 miles is marginal value.

Both HEV and PHEV recharge from braking. Neither typically use the ICE to recharge the battery. To do so less efficient than using the ICE to drive the wheels directly.
 

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If you drive 80-100 miles each day, you will get 25 electric miles EACH day. If you only drive 15 miles per day, then yes you will be fully electric almost all the time, but the total electric miles driven, and thus benefit of PHEV, will nevertheless be lower.
 
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