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2014 Forester CVT
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23 Posts
Discussion Starter #1 (Edited)
Howdy everyone,

Hope you're all doing well!

So I've got about 6000 miles on the car now and I've noticed something a bit odd. Temperature is about 5-14 degrees F. I start the car up and of course, get the standard high revs. Let the car sit for a minute and start to drive. When the car is cold, I've begun the practice of manually shifting the CVT. Having been a diesel driver for many years, I always like to shift at low rpms as possible. Anyway, I'm using the paddles, shifting up and eventually get to 6th gear and 60mph. However, the tach is showing me 2100 rpms which is about 600 rpms higher than is usual on flat highway @ 60mph. And yeah, I pay strict attention to the tach at highway (and other speeds) so I'm sure of the numbers. Now, when the car gets well and truly warmed up, the tach shows 1600rpm at 60. Am I overly concerned or is this transmission holding on to the lower gears too long before shifting up? This phenomenon has caused me to abandon allowing the car to shift itself because it never seems to want to get out of 5th gear - even on the flats.

Thanks very much for your comments.
 

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Cars operate better at a specific temperature set by the manufacturer and they try to get there as fast as possible. The CVT fluid especially is thicker and takes longer to warm up, fluid heat exchange from the engine coolant allows for this to happen faster but they easiest way is to have the engine run at higher RPM's via transmission control. This also includes getting the catalyst system warm as quickly possible as well.

You are negating this and actually causing strain on the system by shifting manually, It boosts pressures in manual mode like any transmission. In my opinion CVT's should only be shifting during sport functions but manually shifting all the time totally negates the purpose of them in the first place. Shifting early doesn't save fuel, technically its lugging the system and uses more fuel for less power produced.

Basically put it in drive until the blue light turns off at least.
 

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Premium Member
'17 Imp Ltd wagon CVT
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1,172 Posts
Howdy everyone,

Hope you're all doing well!

So I've got about 6000 miles on the car now and I've noticed something a bit odd. Temperature is about 5-14 degrees F. I start the car up and of course, get the standard high revs. Let the car sit for a minute and start to drive. When the car is cold, I've begun the practice of manually shifting the CVT. Having been a diesel driver for many years, I always like to shift at low rpms as possible. Anyway, I'm using the paddles, shifting up and eventually get to 6th gear and 60mph. However, the tach is showing me 2100 rpms which is about 600 rpms higher than is usual on flat highway @ 60mph. And yeah, I pay strict attention to the tach at highway (and other speeds) so I'm sure of the numbers. Now, when the car gets well and truly warmed up, the tach shows 1600rpm at 60. Am I overly concerned or is this transmission holding on to the lower gears too long before shifting up? This phenomenon has caused me to abandon allowing the car to shift itself because it never seems to want to get out of 5th gear - even on the flats.

Thanks very much for your comments.
It's working properly. Noted the same thing myself.

Burwood69's advice is good... let the car do its thing and leave it in auto until it warms up completely. Part of the higher RPMs you note is because the torque converter isn't locked up when cold, allowing the revs to be higher. All automatic transmissions are like this, it's just the CVT that makes it so noticeable. Higher revs and an unlocked TC help the fluid to get up to temp.

Patience.
 

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2014 Forester CVT
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23 Posts
Discussion Starter #5
Do you think that doesn't have an influence on gas consommation?
Since, I see that rpm my mpg have raise a bit.

Thank you for you answer
 

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2015 Impreza 5-Door Sport Auto (CVT)
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2,354 Posts
I don't have the paddle shifters and when backing up then going to drive the hesitation is so slight you hardly notice it. This is only in pretty cold weather when engine is dead cold.


If I would complain about this slight hesitiation I would say I would be nitpicking.
 

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Smooshed FOTY 2011
2005 Lifted 2.5 XT 5-Speed MT Dual-Range
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5,734 Posts
A lot of new car makers are actually putting "automatic transmission heaters" in the cars now to get the transmission up to operating temperature for it to operate at it's peak performance and efficiency. They're built to work at a specific temp. Until they get there, you will notice this. My old 4EAT hated the cold weather until it was up to temp. Would hold gears a lot longer.
 

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2014 Forester CVT
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23 Posts
Discussion Starter #8
Thank you everyone

I just wanted to make sure by using that everything was normal. You reassure me. To go to work because I'm 16 km faice which is equivalent to 10 miles and my transmission never pass the "6th" or speed returns to its normal 1600 rpm.

Thank you
 

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2014 2.0 XT yes
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2,752 Posts
The CVTs of the 2.5 and XT also have transmission fluid cooler/heaters.

It looks similar to the oil-coiler under the oil filter attachment on turbo engines.

This diagram is from the TR580 (2.5 CVT):
 

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2014 XTP CVT
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57 Posts
Something the Subaru Mechanic told me the other day may have an effect on this too. Apparently the because of the direct injection the motor actually operates like a diesel when it is cold, the throttle body is held wide open and the engine rpm is controlled 100% by adjusting the fuel mixture, this helps it get to temperature quicker.
 

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2010 2.5X Limited 4-speed Auto
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1,983 Posts
What makes direct injection different from "regular" fuel injection?
 

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'17 Imp Ltd wagon CVT
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1,172 Posts

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2014 2.0 XT yes
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Direct injection totally transforms a turbo engine.

First, you get good detonation resistance, so the car can run a higher compression ratio. For example, the EJ20 engine in my previous car had 8.0:1 compression, and felt very soggy off boost. There's a lot more snap with the FA20-DIT's 10.6:1 compression. Off-boost doesn't last long though, as...

...turbo direct injection engines are able to generate peak-torque fast (<2000 RPM), and hold it there throughout the power band. Basically the fine-grained control over fuel metering (plus other stuff like the variable valve timing) allows the tuner to fill in any lumps or troughs in the power curve with boost. Whereas my EJ20 had sort of a wiggly, hilly torque curve, the FA20-DIT is table-top-flat. That's what makes it nice when you punch it at 60 mph to pass someone. The torque turns on like a switch, and just applies constant thrust (the CVT really accentuates this effect) throughout the maneuver, and before you know it, you are going 90+. Oops.

DI is also apparently good for emissions too, but that's not the reason I'm into it.
 

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2014 Forester CVT
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23 Posts
Discussion Starter #17
Some update about the rpm. Today I did about 25 miles before the rpm goes down to normal. I am really curious about that if its really normal for it to take so long to go down to normal?

Thx
 

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'19 Forester LTD CVT
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3,249 Posts
Some update about the rpm. Today I did about 25 miles before the rpm goes down to normal. I am really curious about that if its really normal for it to take so long to go down to normal?

Thx
It takes a long time for transmissions to warm up. Somewhere on Nasioc there is a guy that ran around during summer and recorded how long it took his transmission to get up to a steady temperature. All said and done the average time was around 70 minutes before the transmission fluid stayed at a steady hot temperature. To be fair, that was a manual. Auto's will heat up faster because of the torque converter (when it is unlocked the RPMs are higher and it produces a lot of heat) but especially when it is cold, it takes a fair amount of time to warm up to operating temp.
 

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2014 Forester CVT
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23 Posts
Discussion Starter #19
So maybe I dont drive long enough each day to see a good gas consommation. It will probably take longer than 25 miles to get the real good mpg of the car.
 
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