Cvt is weird

[Shawn2shawn]

The perceived "unpredictability" of the CVT logic is just the result of relatively complex programming of the powertrain. It uses what could be called some sort of heuristics or AI. The program is trying to guess the driver's intentions based on a multitude of parameters. Such as gas pedal position and rate of change but also a dozen others. Since you are not aware of all the parameters, you may have impression like it's random. It may depend on exactly how abruptly you are mashing the gas, what were you doing a moment ago, what has been the speed of the car, the load on the engine, the gearing, going straight or turning or turning sharp or going uphill, etc. So the algorithm is trying to guess if you are just trying to get a burst of power for passing, or trying to beat a 0-60 time, and it may or may not take your "pedal to the floor" literally, as a "go to the redline" request.

You probably have the best chance of getting the simulated shifts when you do a 0-60 from a dig or very slow roll. Otherwise, the car will do the typical automatic transmission "kickdown" procedure, assuming you are trying to pass, not just trying to get to the redline in a hurry. How the gearing will actually change (whether it's enough to just increase the rpm and boost, or an actual "kickdown" is necessary) will depend on whether the computer judges the acceleration is enough or not.

We are dealing here with an actual computer program, but even in older mechanically controled transmissions the kickdown behavior could be quite complex:
https://www.hotrod.com/articles/pit-stop-automatic-trans-kickdown-cables-really-needed/

So the TL;DR is: it's not unpredictable or random -- it's just more complex than you think. In the CVT civic, optimizing it for a regular naive driver takes priority over a racing/testing/joy-driving assumption.

That's what "automatic" means: it does it for you, but you lose some control.

Idk, I've done pulls with full throttle at the exact spot on the road and its still unpredictable

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[pumpkin]

The question is why is the CVT not doing the same thing when road conditions, tires and driver inputs are exactly the same.

because those three variables are NEVER the exact same,

 

[pumpkin]

so keep praying and hoping for my cvt to blow

there is no praying or hope required,

all that's needed is time, and it ain't on your side,

i know your type, you abuse your vehicle every day, you play around with aftermarket parts that you know nothing about, saying everything is fine, no harm done,

then one day your engine or tranny blows up and you cry like a little girl....then even worse, you come on forums like this blaming honda, and bad mouthing honda for your own stupidity

 

[GermanCivic]

because those three variables are NEVER the exact same,

Of course not 100%, then let those variables be slightly different, still not a good explanation why the CVT sometimes behaves completely different.

 

[gtman]

Over my 40+ year driving career, I've mostly driven manuals with a handful of traditional automatics sprinkled in. This is my first CVT.

At first I hated it because it felt like it had a mind of it's own. But, after a while, I began to appreciate how efficient and well designed it is.

In essense, the transmission's brain is constantly factoring in things like throttle position and load to put the engine at the most efficient rpm range for any given situation.

Does it work perfectly? No. There are hiccups from time to time. But, traditional automatics aren't always perfect either. I can't tell you how many times in hilly areas a traditional auto I drove was confused and constantly hunting for the right gear. Annoying.

 

[Shawn2shawn]

there is no praying or hope required,

all that's needed is time, and it ain't on your side,

i know your type, you abuse your vehicle every day, you play around with aftermarket parts that you know nothing about, saying everything is fine, no harm done,

then one day your engine or tranny blows up and you cry like a little girl....then even worse, you come on forums like this blaming honda, and bad mouthing honda for your own stupidity

U old right? Should be in the corolla section instead of here, @gtman reliability thread has proven the cvt is strong to hold up even tuned and doing multiple pulls, the cvts that are blown are from 99% brake boost, I bet my cvt have more time left than u do.

 

[fkseven]

@pumpkin
Do you know how many blown CVTs we already had here in the forums?

Cvt to Manual Trans gonna come soon to my car......
Cvt is perfectly fine tho

 

[briq4]

So according to the repair manual the "fake shifting" or WOT Step Shift Mode is supposed to function in all driving transmission positions except low...

 

[GermanCivic]

@gtman reliability thread has proven the cvt is strong to hold up even tuned and doing multiple pulls, the cvts that are blown are from 99% brake boost.

What do you mean by brake boost? Having the foot on the brake while revving at the same time? Like this guy is doing before his pulls?

 

[Shawn2shawn]

What do you mean by brake boost? Having the foot on the brake while revving at the same time? Like this guy is doing before his pulls?

Yup that will fooked up your cvt if u do it several times, and also 0-60 in 10 seconds wtf that's awfully slow

 

[bcrichster]

Yup that will fooked up your cvt if u do it several times, and also 0-60 in 10 seconds wtf that's awfully slow

Damn, I'd have sworn TorquePro stated like a 7.4 sec 0-60 for my Sport.. my 1998 Civic takes literally double, around 15sec 0-60 ?

 

[Touring1.5tcivici]

same complaint here. I made a post about the same issues a couple weeks ago. basically the transmissions is so confusing. I said for it to fake shift put it in drive and floor it and midway drop it to sport mode on the gear lever and this will create the fake shift. This car is stupid that it cant simply put out the same feel each time it accelerates. somedays this car impressess me with transmission (only once a month) and the rest are plain garbage and weird. the power delivery is so unpredictable. Oh yeah even when u brake the cvt feels so buggy after a stop, it jerks the car.

 

[Shawn2shawn]

same complaint here. I made a post about the same issues a couple weeks ago. basically the transmissions is so confusing. I said for it to fake shift put it in drive and floor it and midway drop it to sport mode on the gear lever and this will create the fake shift. This car is stupid that it cant simply put out the same feel each time it accelerates. somedays this car impressess me with transmission (only once a month) and the rest are plain garbage and weird. the power delivery is so unpredictable. Oh yeah even when u brake the cvt feels so buggy after a stop, it jerks the car.

True, 2 days ago I was racing my buddy Lexus is 300 rwd and I actually beat him by half a car length but I'm tuned the cvt did the quick gear shift thing and I was in D, he was stock, then last night we raced again literally on the same Winston church hill road and his Lexus destroyed my civic by about 2 car length because the IDIOT CVT decided to approach slowly to redline and stay there it didn't do the fake shift and this was done in same D gear ....so stupid like wtf, how'd you go from beating an IS 300 TO LOSING BY 2 CAR LENGTH. SMH, can't wait to trade in for a Accord 2.0

 

[GermanCivic]

This car is stupid that it cant simply put out the same feel each time it accelerates. somedays this car impressess me with transmission (only once a month) and the rest are plain garbage and weird. the power delivery is so unpredictable. Oh yeah even when u brake the cvt feels so buggy after a stop, it jerks the car.

Maybe it's time for a change of the CVT fluid. When was the last time you changed it?

 

[Shawn2shawn]

Maybe it's time for a change of the CVT fluid. When was the last time you changed it?

Hah change it every 20k km which is overkill, I change it just before winter already, o own the car for 16 months and already did 2 cvt fluid change, 4 oil change and 1 brake fluid change

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