Ktuner Civic Hatchback CVT problem

FK7Turkey

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I have a civic hatch 1.5 t cvt (14k miles) A few days ago I was looking at Ktuner Log files. I noticed a problem with the third and fourth gear shifts.After the third gear quickly shifts into fourth gear and shifts back to third gear.The same problem exists at the beginning of the fourth gear. Anyone have opinion for the situation ?

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r.camlin

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There are no gears on the CVT. That sensor or display unit is irrelevant for you.
 

PEPSIFLAME

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CVT stands for Continuously Variable Transmission.
 

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The CVT doesn't have gears but the whole range of transmission ratios is arbitrarily divided into several ranges called "gears". There is nothing wrong with the gear ratio going a bit back and forth even when the driver is trying to continuously accelerate. Depending on the sensed/computed conditions of rpm, speed, requested throttle, and the load on the engine, the CVT may momentarily go back in transmission ratio if the computer calls for more power/torque. This correction may be very slight, but it may show on the "gear" display as a "downshift" if the arbitrary transmission boundary is crossed even just barely. It doesn't necessarily mean that the ratio actually changed by a whole "gear" worth.

The problem is that the ECU/CVT is not able to predict the future and plan ahead, so it can only react to the varying current conditions. It is also programmed to favor the highest possible gear for fuel economy, so if this turns out to be too optimistic, it may need to correct down.
 


Muscleman

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The CVT doesn't have gears but the whole range of transmission ratios is arbitrarily divided into several ranges called "gears". There is nothing wrong with the gear ratio going a bit back and forth even when the driver is trying to continuously accelerate. Depending on the sensed/computed conditions of rpm, speed, requested throttle, and the load on the engine, the CVT may momentarily go back in transmission ratio if the computer calls for more power/torque. This correction may be very slight, but it may show on the "gear" display as a "downshift" if the arbitrary transmission boundary is crossed even just barely. It doesn't necessarily mean that the ratio actually changed by a whole "gear" worth.

The problem is that the ECU/CVT is not able to predict the future and plan ahead, so it can only react to the varying current conditions. It is also programmed to favor the highest possible gear for fuel economy, so if this turns out to be too optimistic, it may need to correct down.
The cvt doesn't have gears but why is there boost by gear in the map for the cvt?
 

gtman

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Because the "virtual gears" represent certain ratios within the power band. For example, limiting boost in "1st" can help lessen wheelspin off the line.
 

Muscleman

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Because the "virtual gears" represent certain ratios within the power band. For example, limiting boost in "1st" can help lessen wheelspin off the line.
But but is it bad to put the highest psi in the first gear,
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