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2018 Outback Limited 3.6
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Discussion Starter · #1 ·
I'm new to both Subaru and AWD so please tell me if this is normal for a 2018 Outback Limited 3.6 we just started driving.
When driving and I take my foot off the accelerator pedal, the car doesn't feel like it is coasting freely (still in drive gear). It feels like the transmission/engine is holding the car back and gently slowing it down. It seems most noticeable in the 20-40 mph range.
Compared to other CVT cars I've owned, it feels as though it would coast more freely if I slipped it into neutral (which I'm not doing and don't plan to do.)
Everything else seems great, good acceleration and gas mileage in the mid-20s for mixed driving.
Is this just the normal feel of a Subaru CVT?
 

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2015 3.6R Limited w/ES
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3,814 Posts
Both of my Subarus, a 4EAT and my 3.6 with CVT, seem to have a bit more engine braking (without downshifting) than most other auto trans cars I've driven. I've always assumed that was because of the AWD system.
 

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MY20 Subaru Outback 2.5i SE Premium Lineartronic
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39 Posts
It doesn't seem to be limited to the 3.6 as my 2.5 does it too. I'm sure I'll drive round it eventually but it can make stop/start traffic a little less smooth than with a traditional set up.
 

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2017 Outback Touring
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275 Posts
I think my '17 Touring w/83k mi coasts really well. I kill my cruise hundreds of feet before stopping or turning and only shed 20-30% of my speed while coasting.

I was thinking the CVT has to play a major part in this, sensing no throttle, no braking, and knows the wheel spin, then "finding" the perfect coasting gear ratio.
 

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'16 Outback Limited 2.5
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6 Posts
My 2016 OB with 2.5 has the same feeling when letting off the pedal. When I want the feeling of coasting, I’ll let up halfway on the accelerator earlier and it’s satisfying that I may be saving fuel as I’m slowing before letting up completely.
 

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My 2017 the CVT definitely drags slightly butvits clearly programmed to, and nothing compared to how aggressively it engine brakes via the CVT to hold a cruise speed going downhill.

It's definitely not programmed to behave like an unlocked torque converter on a standard auto trans.

The engineers want to keep it tensioned up for some reason. They REALLY want control of cruise speeds.

The design doesn't play nicely with vehicles on cruise in heavy hills that are behind you expecting everyone will roll freewheel downhill.

They'll be on your bumper wondering why you downshifted.

Easiest way to get anyone to pass me on our rural two lanes in rolling hills is to set the cruise and ignore it. They be flying by at the second hill.
 

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2018 OB 2.5 Ltd, No Eyesight, No Navigation
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3,461 Posts
While coasting on flat land, I do not get an engine braking sensation at all on my 2018 OB 2.5 Limited, no Eyesight. While city driving and see a red light, I will often start coasting from a quarter mile away. Yeah, people zoom by me in anger only to greet me 20 seconds later at the stop light ahead. I see no point in speeding to the next light only to slam on the brakes. Anyway, I feel the car floating on its momentum without engine braking.

Regarding the cruise control, the strict maintenance of the speed on hills is one thing I really like. The driver always has the option of toggling cruise control on-and-off. With a little practice, the toggling becomes second nature, but I typically enjoy the steady speed maintenance. There are some hilly roads around me with strict speed control, specifically because people tend to speed way above the limit on the downhill portions. Subaru's strict cruise control makes the drive easy and ticket-free.
 

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'15 Outback 2.5i Premium
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One thing I heard soon after getting the Subaru that surprised me, but appears to be true, is that if you're coasting in gear, fuel to the engine gets shut off - the engine isn't even running, it's being turned by the wheels, but not firing.

Once your speed drops to about 15 MPH, the fuel is turned back on and it starts up on its own again. Go to some deserted section of straight road where you can safely drive at low speed and try this experiment: set the multi-function display on the panel to show instantaneous MPG and, on a long straight section, from about 40 or 50 MPH, take your foot off the gas and watch the fuel economy jump to 99.9 MPG (that's the highest it can display - it's actually infinity) as you decelerate. Once your speed drops below 20, at some point you may (or may not) feel a slight shudder, and the economy drops from 99.9 to 50 or so (in my 2.5, anyway; YMMV) because you are starting to consume fuel again. I never noticed that shudder until I started looking for it - it's pretty subtle.

If, instead, you coast in neutral, you don't see that 99.9 MPG, because it has to feed the engine gas to keep it turning.

The upshot is that your car really is "dragging" because engine braking is greater than you may be used to. The engine is not generating motive power at all - instead, it's absorbing it.
 

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2012 OB , 2017 Impreza
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3,562 Posts
The CVT system communicates with all the other computers within the vehicle. Based on MANY inputs, the CVT will change gear-ratios when the throttle is lifted.

I have observed these 'inputs' to include:
  • Braking pressure
  • grade (uphill/downhill)
  • vehicle speed
It seems the engineers programmed the system to try to prevent the vehicle from speeding up while going downhill. Also, if I jab the brakes, the CVT tends to downshift to help the vehicle slow down.
 

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2012 OB , 2017 Impreza
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One thing I heard soon after getting the Subaru that surprised me, but appears to be true, is that if you're coasting in gear, fuel to the engine gets shut off - the engine isn't even running, it's being turned by the wheels, but not firing.
Nothing new -- Fuel-injected vehicles have been doing this for over 20 years now. It is an easy way to improve MPG. (Why inject fuel when it will simply pass thru the engine unburned?)

Some vehicles also turn on the alternator 'full blast' when decelerating in an effort to capture/store energy in the battery.
Likewise, the alternator is turned OFF during accelleration to provide more power to the wheels.

The nature of having EVERYTHING on the vehicle sensed and computer-controlled provides engineers with all kinds of ways to manipulate and control the vehicle systems.

I assume you know that the Subaru AWD system automaticcly applies the brakes on INDIVIDUAL WHEELS to prevent tire-slippage. (The ABS system can detect when a tire is spinning faster than the others and apply the brakes to that one wheel to correct it)

You may not be aware that some Subies actually apply the the brake to the front-inside wheel when you turn the steering-wheel. This helps to 'pull' the vehicle around corners.

This is one reason people have noted that the brakes can wear out MUCH faster than expected....especially the rear brakes which used to last 2X the front ones. These folks do not realize that their driving-habits are wearing out the brakes (even if they are not touching the brake-pedal)
 

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2018 OB 2.5 Ltd, No Eyesight, No Navigation
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For the cars experiencing engine braking while coasting, perhaps the car’s computer has learned your driving habits as being a hard braker (like racing to the next red light), and the computer instructs the car to engine brake for you more often to help you out.

As explained above, I will start coasting for a stoplight from a quarter mile mile out. There is a street near me that has a stretch of about 10 stop lights. Sometimes, I can time my coast such that I don’t even apply the brakes once. And sometimes, I beat the folks racing between intersections because when I get to the red light, I am often already rolling. So I go ahead, coast for the next red light way up there, watch the angry racers pass, go ahead at the green light, and repeat.
 

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2016 Outback Premium 2.5 CVT w/EyeSight+SRVD
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7,542 Posts
When driving and I take my foot off the accelerator pedal, the car doesn't feel like it is coasting freely (still in drive gear). It feels like the transmission/engine is holding the car back and gently slowing it down. It seems most noticeable in the 20-40 mph range.
...
Is this just the normal feel of a Subaru CVT?
It's normal. In this respect, the Subaru CVT acts just like a manual transmission, and for the same reasons. At speeds above about 15 mph, the torque converter lockup clutch is always engaged, so there is a solid connection all the way from the engine crankshaft to the tire contact patch(es) at the road surface. (By contrast, most conventional automatic transmissions will disengage the TC clutch when decelerating and some even include sprag clutches to allow limited free-wheeling during deceleration.)

Nothing new -- Fuel-injected vehicles have been doing this for over 20 years now. It is an easy way to improve MPG. (Why inject fuel when it will simply pass thru the engine unburned?)
It's also an excellent way to reduce exhaust emissions, without any bad side effects. No fuel injected during closed-throttle deceleration means zero combustion products and unburned fuel coming out of the exhaust pipe.

FWIW, my 1969 Porsche 911S ... with its beautiful, expensive, and complex Bosch all-mechanical fuel injection ... would shut off fuel delivery whenever the throttle plate was fully closed and the engine rpm was above about 1500. You could hear a distinct crackle from the exhaust when fuel delivery resumed. This was more than 50 years ago!
 

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'19 Premium, 2.5
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132 Posts
...the car doesn't feel like it is coasting freely (still in drive gear). It feels like the transmission/engine is holding the car back and gently slowing it down....
My experience has been the opposite. My 2.5i rolls more freely with less engine braking than any of my previous cars (conventional automatics). While that my up my MPGs just slightly, it makes the car feel less responsive. I don't prefer it this way but I've adjusted...mostly.
 

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2012 OB , 2017 Impreza
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3,562 Posts
...perhaps the car’s computer has learned your driving habits...
Good point!!!

The vehicle onboard computer network not only can measure and react dynamically to the sensors... There is memory which creates 'spreadsheets' for defined conditions.

These spreadsheet maps may be based on:
  • air-temperature
  • brake-pressure
  • Incline/decline
  • Steering angle
  • Pitch, Yaw, and Sway
  • Throttle position
  • acceleration / deceleration forces
  • wheel speeds
  • ...etc
------------------


For what it is worth... The engine control computer also memorizes and reacts to maintain the emissions within parameters. (and illuminates the CEL if it cannot make the corrections on its own)
 

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2012 OB , 2017 Impreza
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3,562 Posts
FWIW, my 1969 Porsche 911S ... with its beautiful, expensive, and complex Bosch all-mechanical fuel injection...
I owned several Volkswagen's with the Bosch all-mechanical fuel injection. It was a hydro-mechanical marvel using just air, fuel, flow, and pressure to determine how much fuel to inject. The only electric part was the FUEL PUMP.

The first vehicles I ever owned which started at subzero temperatures by just turning the key....(NEVER touch the throttle whilst starting)

I recall testing and replacing fuel-injectors on these things. Use magnet to lift the 'flapper' which measures airflow to force the injectors to spray.

If vehicle manufacturers did not use Bosh.... they did not have fuel injection. (Of course, Mr. Bosch also invented the spark-plug)

Relavant to THIS discussion, the mechanical fuel-injection did NOT know when the throttle was released besides the reduction of airflow. The injectors did NOT shut off during deceleration which caused that delicious backfiring. (fuel burning in the exhaust pipe instead of engine)
 

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Although subtle, my 2014 2.5cvt does this also. I think it is by design, but mine does not seem to do it at highway speeds. It threw off my timing for coasting up to a stop sign etc. , but I have gotten used to it. I guess it will help the brakes last a bit longer. I agree with previous post that it is to control down hill speed, and maybe it is to help control traction when coasting on slippery roads, since every time you touch the brakes you have a higher chance of sliding or loosing trac.
 

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2017 Outback, 2.5L, Auto; 2018 Forester, 2.5L, Auto (for Mama); 2005 Baja, 2.5 Turbo, Manual
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One thing I heard soon after getting the Subaru that surprised me, but appears to be true, is that if you're coasting in gear, fuel to the engine gets shut off - the engine isn't even running, it's being turned by the wheels, but not firing.

Once your speed drops to about 15 MPH, the fuel is turned back on and it starts up on its own again. Go to some deserted section of straight road where you can safely drive at low speed and try this experiment: set the multi-function display on the panel to show instantaneous MPG and, on a long straight section, from about 40 or 50 MPH, take your foot off the gas and watch the fuel economy jump to 99.9 MPG (that's the highest it can display - it's actually infinity) as you decelerate. Once your speed drops below 20, at some point you may (or may not) feel a slight shudder, and the economy drops from 99.9 to 50 or so (in my 2.5, anyway; YMMV) because you are starting to consume fuel again. I never noticed that shudder until I started looking for it - it's pretty subtle.

If, instead, you coast in neutral, you don't see that 99.9 MPG, because it has to feed the engine gas to keep it turning.

The upshot is that your car really is "dragging" because engine braking is greater than you may be used to. The engine is not generating motive power at all - instead, it's absorbing it.
shutting off the fuel when coasting is common with lots of fuel injection cars - for both emissions and mileage. My old 81 BMW did it.
Pressing the accelerator pedal just a tiny bit gets the throttle off the idle stop and the car will coast more freely. That's my common practice with cruise control and hills. ;-)
 

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2018 OB 2.5 Ltd eyesight
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Nothing new -- Fuel-injected vehicles have been doing this for over 20 years now. It is an easy way to improve MPG. (Why inject fuel when it will simply pass thru the engine unburned?)

Some vehicles also turn on the alternator 'full blast' when decelerating in an effort to capture/store energy in the battery.
Likewise, the alternator is turned OFF during accelleration to provide more power to the wheels.

The nature of having EVERYTHING on the vehicle sensed and computer-controlled provides engineers with all kinds of ways to manipulate and control the vehicle systems.

I assume you know that the Subaru AWD system automaticcly applies the brakes on INDIVIDUAL WHEELS to prevent tire-slippage. (The ABS system can detect when a tire is spinning faster than the others and apply the brakes to that one wheel to correct it)

You may not be aware that some Subies actually apply the the brake to the front-inside wheel when you turn the steering-wheel. This helps to 'pull' the vehicle around corners.

This is one reason people have noted that the brakes can wear out MUCH faster than expected....especially the rear brakes which used to last 2X the front ones. These folks do not realize that their driving-habits are wearing out the brakes (even if they are not touching the brake-pedal)
Well, the engineers did not consider that coasting to a red light saves fuel over cruising with applied power until the last minute. The engine braking makes it impossible to coast to red lights at the point I would like to, hence wastes fuel. BTW, this is also consistent with how the engineers programmed adaptive cruise -- the car waits way too long before applying brakes if the guy ahead has slowed down, which can be a surprise deceleration to the guy behind you, and yes, the eyesight has already acquired the guy in front.
 

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I experienced this on my 2005 OB but it seems better on my 2015. It drove me nuts as it would never let the vehicle coast over the set cruise control speed even on extended down hills. One of my least favorite 'features'. It would coast better if I turned off cruise so it was intentionally holding speed down.
 
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