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Hey all, first time posting in this section. I was wondering if anyone on the forums has experienced their Impreza's CVT being sluggish.
I have almost 16k miles (although not a lot) on my 2017 Sport. When driving, I have my accelerator LCD screen on the top center console up to see how heavy my foot is. Up until recently, when my foot is at 40% throttle my transmission just holds up 2k RPMs and i feel no acceleration whatsoever. Before this feeling, I recalled noticing how responsive the CVT was in normal Drive mode. At 30% throttle and above the transmission would "shift" down gears and raise the RPMs up to accelerate and do it's "mimicking of shifts" but the last week or so 80% of my drives have consisted of that constant no acceleration at 2k RPMs while on throttle.
I was wondering if anyone else experienced this, or if anyone knows what could be a cause. Thank you.
 

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Hey all, first time posting in this section. I was wondering if anyone on the forums has experienced their Impreza's CVT being sluggish.
I have almost 16k miles (although not a lot) on my 2017 Sport. When driving, I have my accelerator LCD screen on the top center console up to see how heavy my foot is. Up until recently, when my foot is at 40% throttle my transmission just holds up 2k RPMs and i feel no acceleration whatsoever. Before this feeling, I recalled noticing how responsive the CVT was in normal Drive mode. At 30% throttle and above the transmission would "shift" down gears and raise the RPMs up to accelerate and do it's "mimicking of shifts" but the last week or so 80% of my drives have consisted of that constant no acceleration at 2k RPMs while on throttle.
I was wondering if anyone else experienced this, or if anyone knows what could be a cause. Thank you.

Ahhh I have been having the same problem are you still under warranty?
 

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The computer will 'limit' the CVT shifting until the TRANSMISSION is fully warmed up.
Lets never forget that when the CVT fluid is not up to operating-temparture, the chain can slip on the sheaves. The computer is programmed to NOT allow this to happen.

The TRANSMISSION is not easy to heat up in colder ambient temperatures. (because it is a large aluminum heat-sink) I have noted that when ambient temp. falls below 55F, it takes several miles of driving before the CVT is 'allowed' to shift normally.

When ambient temp is below 10F, I can drive for 20 miles and the RPMs will remain around 2000 due to cold xMission fluid. Adding a cover over the radiator-grille REALLY helps the CVT come up to temp. quicker.

Technical stuff:
There is a heat-exchanger between the antifreeze/xMission-fluid.
1) During warm ambient temps. - the heat from the xMission is shed into the antifreeze out through the radiator.
2) During cold ambient temps. - the heat of the engine is xferred to the xMission. (radiator is hardly even needed becasue the xMission is cooling the engine.)

What you are sensing is #2 above..... the xMission is sucking heat from the engine in an effort to warm the CVT fluid before 'normal' shifting is allowed to take place.

If you turn OFF the heat into the cabin... there is more heat from the engine available to warm up the CVT fluid.... hence the shifting will sooner become 'normal'.

All of the above are side-effects of a very efficent engine.... During cold ambient tempartures, there is not a lot of excess heat generated by the engine to heat both the cabin AND the xMission.
 

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Thanks BruceP. I think this explains the situation when the CVT/Engine is not warmed up.

I also notice that if I've been accelerating particularly fast on the highway, and then come off the highway to regular roads, it suddenly does something similar. In this case, I would imagine that the CVT would be very warm as it seems to perform just fine. But once I get back to lower speeds, this seems to happen...

Does it take time for the ECU to register that I'm no longer accelerating as much (I'm guess it's anticipating that I'll be stepping on it when I don't and thus was expecting me to go faster but the RPM just stays there?) Not sure if I've described it in an understandable way. I'll try again if not...
 

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I am not clear on what you are describing..... but I can tell you that there are yaw sensors in the vehicle. This means the computer not only 'knows' which direction the steering is pointed... but also can sense vehicle direction (up/down/sideways) These sensors are used for the ABS braking-system and for the AWD system operation.

It seems that the these sensors are also utilized to determine if the vehicle is pointing UP-vs-DOWN hill.

For example, when I lift off the throttle while going downhill, the CVT will 'downshift' to keep the vehicle from speeding up too much. (Just as I would do while driving manual xMission)

I have also noted that the computer tends to keep RPMs increased anticipating that I may be accellerating under certain conditions.

Also, if the xMission gets too hot, the RPMs may be increased to flow more antifreeze and CVT fluid. This would help the heat-exchanger to do its job. (heat-exchanger works better as the fluid flow is increased.)

I guess what I am saying is that the Subaru engineers have programmed several situations where the CVT will modify gear-ratios....such as based on xMission temp, hills or even ambient temperature. I would think what you are experiencing is 'normal' operation and nothing to worry about.
 
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