CVT rough "shift" in stop and go traffic

[EastBayCivic]

Didn't get to drive it at all today!

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[omens]

When in sport mode I notice when I’m driving at mild speeds, around 45 and under, when I let off the gas I feel a mild jerk, almost as if the CVT is attempting to simulate a downshift? I assume it’s normal as my buddies CVT does the same thing, I was a little worried before driving his though.

 

[schmiddr2]

Lol man where did you get a "clutch" from? It uses a torque converter

Yeah, the only thing is that there is no clutch.

Where did you get that it doesn't have a clutch disc? Really, where, I'd like to read up on it.

https://www.hondapartsnow.com/parts...x-hdm-cvt-kl-cvt/clutch-torque-converter.html

 

[Gruber]

My CVT only jerks when braking hard and releasing near a stop...which (I think) is normal. You definitely want to get it checked out you probably have low fluid in there.

+1, exactly my experience. No jerking in the accelerating situation as described, and I saw the jerking when braking to a crawling speed only once, maybe 2 times. I avoid suddenly releasing the brake at a very low speed after relatively hard braking. In a typical braking before a red light or crossing or a slow car, I try to either brake to stop completely, or, when I want to continue after reaching a very low walking speed, I try to release the brake gently.

 

[messenio]

Hey everyone,

Sometimes when I am traveling at low speed (1-8mph) in stop and go traffic the car will shake or jerk when I give it a little gas.

One of the best examples is when the cars in front of you are stopped so you kind of just coast behind them at low speed (maybe braking a little too), you see that they are moving again, and then give it some gas to keep the car moving into that space that was just created. When I give it a little gas in that situation the car sometimes jerks, jolts, or shakes, kind of like a rough shift, as it starts moving forward. It definitely doesnt happen every time. I also haven't gone to any length to try and recreate it.

It doesn't happen when I'm completely stopped and then give it gas. It also doesn't do it when I'm decelerating at higher speeds and then giving it gas. Maybe this is some kind of low-speed momenum related thing?

Maybe it's completely normal and I just dont experience it much because ~90% of the car's miles are highway and backroads (the wife and I are using another car for the concrete jungles). This is also my first CVT.

Anyways, I'm wondering if anyone has experiences similar to this and whether or not it is an issue. Thanks in advance for your input!

Dropping in to say that I've experienced this as well. It happens at low speed when I either press the gas or brake and come to a stop. It's a back and forth jerking motion that only happens occasionally. I wasn't sure if it was normal or not, but judging by the opinions in this thread maybe it needs to be looked at...?

 

[augustus]

My car does the jerk. If I stop very hard but try to ease up on the brake at the last second to smooth out the stop it will do it, I would call it a lurch, but one man's lurch is another's jerk It's done it at other times, but I can't repeat those.

 

[BogdanM]

Where did you get that it doesn't have a clutch disc? Really, where, I'd like to read up on it.

https://www.hondapartsnow.com/parts...x-hdm-cvt-kl-cvt/clutch-torque-converter.html

Please note that you are "reading" the diagram wrong. Look into parts list below and you will find nothing related to the clutch on the CVT.
As a counter example, please see the link below (changed the car to a 4dr SI, so manual transmission):
https://www.hondapartsnow.com/parts-list/2018-honda-civic-4dr_si-ka-6mt/clutch-torque-converter.html

How many manual transmissions with torque converters have you seen so far?
See that now if you hover the clutch assembly parts you get their descriptions / part no. and if you do the same to the torque converter, they seem inactive? Now take a look at the link you've provided, see if you can hover the clutch assembly parts vs the torque converter ones.

 

[HatchorNada]

When should we be replacing the CVT fluid on this thing? And the coolant? One of these needs replacing in the 25-30k range. And obviously one will affect the shifting.

 

[civicls]

When should we be replacing the CVT fluid on this thing? And the coolant? One of these needs replacing in the 25-30k range. And obviously one will affect the shifting.

Follow the MM and your life will be much easier.

 

[HatchorNada]

Follow the MM and your life will be much easier.

NO, that is also what got a lot of 7th gen Accord owners in trouble too. Don't believe everything you read. I was referring to early preventative maintenance not the do do bird one.

 

[RobbJK88]

I kind of get this issue if i'm going (especially uphill, like an exit ramp) in stop and go traffic... coasting and then barely touch the gas the car kind of "jumps" or jolts forward. Best way i can describe it is like the clutch is abruptly engaged after being disengaged while coasting. It's always done it, so i assume it's just one of those little quirks of the CVT.

 

[EastBayCivic]

Wow sounds like a lot of people are having similar experiences. I guess it's normal-ish.

 

[Charley-TX]

Yes. Mine does it too.
When you are costing you could have the torque converter (clutch) locked even at slow speed. But when you try to accelerate it will unlock + most likely will adjust the cones on the CVT to a different ratio. This will b the cause of the jerkiness.
I can duplicate this just about every time I want to when pulling up to my garage.
Come home on a downhill road and my driveway has a slight upslope. I pretty much roll up the slope without throttle. But there is a 1-inch lip on the concrete inside the garage (to prevent rainwater to flow in) so I have to give it a touch of throttle to roll into the garage. There is a jerking or lurching every time.

PS: your CVT has a fill hole on the top. No dip stick.
You have to follow a procedure to accurately check the level. The car has to be warmed up, and there is a fluid level check bolt that you have to remove, CVT fluid will drip out when at the correct level. You have to get under the car to get to this check bolt on the 1.5T model.

PS2: yes the CVT has a torque converter which allows torque amplification and "fluid slip". But slipping is bad (edit* slipping is ineffective and generates heat)
when slipping is not needed or desired. a clutch will lock the two halves or slipping halves of the converter together.

 

[EastBayCivic]

Yes. Mine does it too.
When you are costing you could have the torque converter (clutch) locked even at slow speed. But when you try to accelerate it will unlock + most likely will adjust the cones on the CVT to a different ratio. This will b the cause of the jerkiness.
I can duplicate this just about every time I want to when pulling up to my garage.
Come home on a downhill road and my driveway has a slight upslope. I pretty much roll up the slope without throttle. But there is a 1-inch lip on the concrete inside the garage (to prevent rainwater to flow in) so I have to give it a touch of throttle to roll into the garage. There is a jerking or lurching every time.

PS: your CVT has a fill hole on the top. No dip stick.
You have to follow a procedure to accurately check the level. The car has to be warmed up, and there is a fluid level check bolt that you have to remove, CVT fluid will drip out when at the correct level. You have to get under the car to get to this check bolt on the 1.5T model.

PS2: yes the CVT has a torque converter which allows torque amplification and "fluid slip". But slipping is bad.
when slipping is not needed or desired. a clutch will lock the two halves or slipping halves of the converter together.

Thanks for your very descriptive post! I am further convinced that this behavior is common. I wonder if it has the potential to evolve into something else?

 

[schmiddr2]

Clutch on CVT? where u get your weed from?

Canada.

I'm not saying clutch like to change gears, no shifting is obvious. But it seems like at slower speeds the CVT disengages, then letting off the brake I can feel the CVT engage after a fraction of a second. This feel reminds of shifting up in a manual trans; that's why I was careful to type clutch in quotations. I think it may be better stated as "free wheeling" when not under load. Either way it's not enjoyable, but getting 40mpg/17kpl is nice.

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