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Discussion Starter #1
since I got very acquainted with Mo this past week (see roadtrip thread), I'd like to ask a couple CVT things I'm not familiar with:

1. when very gently taking off from stop, say around 1500 RPM, i get a little groan out of the cvt for a second or so - is this normal? It *does* kinda remind me of the slight shudder and sound of 1st gear engaging on a manual tranny...

2. continuing to accelerate very gently (say, if traffic ahead is just moving really slow off the line) I noticed several times, just a little hesitation in the acceleration "pull", but couldn't tell if it was actually just the CVT going through a couple ratios, or maybe some injection spurts, or if it was really the road and not the car.

thanks!
 

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When accelerating slowly from a stop, the CVT is programmed to "lock up " the torque converter very quickly. This drops the RPM and creates a slight shudder or lack of smoothness; it also causes the engine to "lug"because the RPMs are well below the power band . In stop and go slow moving traffic, I avoid this to some extent by using Ds.
 

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Discussion Starter #3
senza said:
When accelerating slowly from a stop, the CVT is programmed to "lock up " the torque converter very quickly. This drops the RPM and creates a slight shudder or lack of smoothness; it also causes the engine to "lug"because the RPMs are well below the power band . In stop and go slow moving traffic, I avoid this to some extent by using Ds.
Well in that case it sounds like I'm experiencing a normal phenomenon. Thanks for the clarification!
 

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the torque converter locks up at appr. 18 mph. And yes you will notice a drop in engine RPM. Once the TQ is locked you can feel "stronger" engine pull - or at least that is how I would describe it.

Also the TQ does not locks up till CVT reaches operating temperature.

just my 2c......
 

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The Accelerator is "Drive by Wire" in that you make a request to the system and it decides how much to actually provide the engine. From a stop, the engine power is limited to prevent a high-torque condition to be present on the CVT. Not only does this extend the life of the CVT and reduce the chance of damage from macroslip, it does the same for the tires on the road, so while it's not as exciting, I find the launch from a stop to be very effective.

At least, that's my understanding....:)
 
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