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I’ve been getting better gas mileage w/ the Coronavirus treatment. Hovering at 21mpg steady, 20.5mpg before, because less people on hwy with less stop/go.

I prefer to be working from home but if this crisis keep going for the next months, I’ll hit 22mpg.

Oh... and gas is so cheap right now; pumped 1.68/gal four days ago!!
 

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I wish the roads were like this all the time! SO nice to have traffic levels like they were 15 years ago and less.
 

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CVTs have been around a long time. I first came across them in the early '60s on snowmobiles and ATVs. Those were rubber belt types, of course. These would change ratio based on the the action of fly-weights that would change the pulley flange spacing as a function of rpm. There are other types as well.

I think Nissan was the first major manufacturer to put a CVT in a main stream full size vehicle, the Murano, back in 2002.
I found an interesting read: Continuously variable transmission - Wikipedia

Go down to the history section, turn out CVTs are older than cars, and one of the first to offer it on a modern production car was... Subaru in 1987.
I actually enjoyed reading the whole thing, I recommend that section.
 

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I’ve been getting better gas mileage w/ the Coronavirus treatment. Hovering at 21mpg steady, 20.5mpg before, because less people on hwy with less stop/go.

I prefer to be working from home but if this crisis keep going for the next months, I’ll hit 22mpg.

Oh... and gas is so cheap right now; pumped 1.68/gal four days ago!!
I'm not getting better mpg because working from home, and kids not going to school my wife's Ascent hasn't started since Friday past week! Now that's some savings in gas!
That reminds me: I better not forget to drive it a bit to charge the battery...
 

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I found an interesting read: Continuously variable transmission - Wikipedia

Go down to the history section, turn out CVTs are older than cars, and one of the first to offer it on a modern production car was... Subaru in 1987.
I actually enjoyed reading the whole thing, I recommend that section.
Yep, the Sambar and Justy, among others, used a CVT. You can see a CVT based 1992 Sambar T275 with the VW Samba conversion kit installed in my video of the Subaru Mini Museum at Tom Wood Subaru. It is the van version of the Sambar, as opposed to the flatbed pickup version.

 

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I was not aware that there is an ECU flash available for a 2020 model. Does the repair order from your dealer list any details -- like a part number of a program flash or anything like that? What is the build month and year of your Ascent?
I received a recall notice and took my 2020 Ascent Touring in on Feb 10, 2020, for ECU Reprogramming C1424. Honestly, I have not noticed any changes in performance or mileage, but I will be more observant. With the "lockdown" I have not been driving much for a few weeks. One other problem, and the reason I contacted the dealer in the first place, was a brake noise which was getting worse as time went on. It only occurred when the car was just about to come to a stop. The service supervisor told me that Subaru is aware of the problem and it is the brake pads. Subaru will be replacing them in the very near future. Something to do with the pad compound. Is anyone experiencing this brake noise? Sorry, if off-topic.
 

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I received a recall notice and took my 2020 Ascent Touring in on Feb 10, 2020, for ECU Reprogramming C1424. Honestly, I have not noticed any changes in performance or mileage, but I will be more observant. With the "lockdown" I have not been driving much for a few weeks. One other problem, and the reason I contacted the dealer in the first place, was a brake noise which was getting worse as time went on. It only occurred when the car was just about to come to a stop. The service supervisor told me that Subaru is aware of the problem and it is the brake pads. Subaru will be replacing them in the very near future. Something to do with the pad compound. Is anyone experiencing this brake noise? Sorry, if off-topic.
what was your build date
 

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I figured we had the "poor MPG" and "my MPG is great" threads, figured I'd start a bridge/fixed thread.

Here is the original issues at hand for my 2020 Limited, and I believe a lot of you
  1. Overly sensitive throttle, impossible to precisely vary RPMs below 2,400rpm
  2. RPMs too high when cruising in city or hwy, manual shifting would easily lower by 500rpms or more
  3. Poor gas mileage (12-14mpg) in the city, even when using cruise control
  4. Poor gas mileage on the hwy (19-21mpg MAX), even when using cruise control 99% of the time
  5. Erratic and increasing RPMs when going up a hill for no apparent reason, even when reducing throttle
Last week I had the ECU Reprogramming recall performed and immediately I knew we were getting better MPG. After a weeks worth of driving this is what has been corrected (praises respective to complaints):
  1. Very easy to control lower RPMS, engine no longer goes from tons of power at 2,500+rpms to bogging at 1,500rpms - the bogging issue has not occurred once when it used to happen multiple times per day
  2. RPMs when using cruise (or not) in city and hwy are MUCH lower and where they should be - I can cruise through the city around 35-40mpg and the engine will be at 1,200rpms
  3. Gas mileage in the city, using the same habbits and routes, is now 20mpg every day
  4. HWY MPG is not fully vetted, partly due to COVID-19 and limited travel, but I have seen an improvement - just no hard data
  5. RPMs no longer go crazy when going up a typical hill, they stay constant even when letting off the throttle
Now, I have a few myths to bust (yes, not scientific) which some members claimed are the reasons for poor MPG:
  • Ascent is still being warmed up a few minutes prior to leaving for work and prior to coming home.
  • Driving style was not a factor. We continue to drive the Ascent the same as we did before, using a lot of cruise control still in the city and on the hwy. I attribute this to the lower RPMs for acceleration and cruising speed.
  • Temperature is still roughly the same. No crazy delta in the temp, still continue to have a lot of sub-freezing temps.
All in all, my wife and I are VERY happy with the improved MPG. She no longer says "we sold the Yukon to get rid of the 12-14mpg city driving".
I'm wondering - are you basing your MPG on what the car's digital readout says, or on your own calculations? I think that, before the recall, I was getting around 21 mpg (rural roads - less stop/go than city). After the recall, my Average MPG according to my digital readout is @ 26 mpg.... I really doubt this is true! That's better than my Outback was...
 

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To propel a vehicle against friction and aerodynamic drag, or up a hill, takes torque and rpm. The product of torque and rpm is power. A given situation will require a given power, and the that power can be acheived either at a lower rpm with higher torque, or a higher rpm with lower torque. Up to a point, the latter is often less stressful on a drivetrain.
Given the turbo engine I think there's a lot less strain on the engine above 2,200rpm that there is at 1,800 rpm. More boost will make it a bit more efficient than "straining" at a lower rpm before the boost comes on. If you stay at the lower rpm you have to dump more gas in to get the same power vs raising the rpm a bit and getting the help of the boost.

As for more rpm with a lower torque causing less strain on a drivetrain, professional cyclists know this well! When I was biking like mad (4,000 miles/year) we quickly learned that a high cadence (rpm of the pedals) was much more efficient than a lower cadence. You can ride much farther and faster doing 90-100rpm than you can doing 40-60rpm. Your legs push much less on each go around so it's less strain on the muscles. The only limit to cadence is being able to keep it smooth. After much practice we got to where we could do 120rpm easily and we did so much better!

If we ever get an update to the CVT to act like a CVT, then it can hit the sweet spot for the given power input and just stay there. Need steady acceleration, hit 2,500 rpm. Need really fast acceleration, bump it up to 4-5k and stay there. Smooth power makes such a nice driving experience for passengers. It's one of the great features of the Teslas. No gears, so smooth power delivery from 0-100!
 

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If we ever get an update to the CVT to act like a CVT...
Biggest fault with the Ascent and all the new FA24DIT Subarus by far.SO disappointing we don't have the different driving modes (i/S/S#) etc.
And they'll never fix it going backwards. Very frustrating since I've OWNED a turbo Subaru with those modes and know what we're missing with the CVT.
 

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Biggest fault with the Ascent and all the new FA24DIT Subarus by far.SO disappointing we don't have the different driving modes (i/S/S#) etc.
And they'll never fix it going backwards. Very frustrating since I've OWNED a turbo Subaru with those modes and know what we're missing with the CVT.
I wish they would just give us a dealer flash to change the mode.

Heck I would pay $100 to do it.... even $200!
 

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Don't know the build date. How can I find that out?
It's on two different decals on the inside of the driver's door. The ones listing the tire pressure. Both should give the build month and the build year (such as 01/20).

If we ever get an update to the CVT to act like a CVT, then it can hit the sweet spot for the given power input and just stay there. Need steady acceleration, hit 2,500 rpm. Need really fast acceleration, bump it up to 4-5k and stay there.
Our transmission (02/20 build) does act like a CVT almost all the time. It's only if I give it about 60% throttle or more that it will fake the shifts. And that much throttle is really too much for many driving situations anyway. Ours will accelerate up a hill holding a steady 2,500 RPM doing it. It won't hold a steady 4,000 RPM or more because it needs too much throttle to get there, and it'll get into the fake shift mode then. Other than reading about it, I wouldn't have known ours faked the shifting unless I specifically tried it with heavy throttle. In most situations, we're not beyond about 30-40% at the most (and below 2,500 RPM almost all the time), and that's very much "CVT territory" for our transmission programming. It does seem like they've adjusted the programming over time on these things.

I agree completely with the drive mode button. Like the paddle shifters, it really doesn't cost much to provide the button. Most may not use it, but some will. And it would bring a lot of joy and satisfaction to those who would like it.
 

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Biggest fault with the Ascent and all the new FA24DIT Subarus by far.SO disappointing we don't have the different driving modes (i/S/S#) etc.
And they'll never fix it going backwards. Very frustrating since I've OWNED a turbo Subaru with those modes and know what we're missing with the CVT.
Maybe it will migrate to the Ascent. It's appeared in the Foz line.
 

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I didn't have poor mileage prior to the re-programming, but from all appearances, I'm still doing as good, if not better than before it. I still have the issue with the engine RPM wanting to increase dramatically when moving uphill at a slow rate of speed, such as an area I need to pass through when going into town to drop my daughter off from work...uphill, 25mph limit, school zone. Interestingly, I didn't have that happen when I had a MY20 Ascent loaner for a day awhile back.
 

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Our transmission (02/20 build) does act like a CVT almost all the time. It's only if I give it about 60% throttle or more that it will fake the shifts. And that much throttle is really too much for many driving situations anyway. Ours will accelerate up a hill holding a steady 2,500 RPM doing it. It won't hold a steady 4,000 RPM or more because it needs too much throttle to get there, and it'll get into the fake shift mode then. Other than reading about it, I wouldn't have known ours faked the shifting unless I specifically tried it with heavy throttle. In most situations, we're not beyond about 30-40% at the most (and below 2,500 RPM almost all the time), and that's very much "CVT territory" for our transmission programming. It does seem like they've adjusted the programming over time on these things.

I agree completely with the drive mode button. Like the paddle shifters, it really doesn't cost much to provide the button. Most may not use it, but some will. And it would bring a lot of joy and satisfaction to those who would like it.
With my 2019 (Sept 2018) before the recent updates, it would fake shift harshly if over about 20% throttle. With the latest updates it seems more like 30-35% throttle and they shifts are much softer and definitely don't lurch as much.

I can drive it under the "fake shift" threshold, but I often like to go above that but it would be really nice if it was smoother for passengers! :D
 

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I’ve been getting better gas mileage w/ the Coronavirus treatment. Hovering at 21mpg steady, 20.5mpg before, because less people on hwy with less stop/go.
I'm seeing the opposite here!
Normally traffic lights on the main strip here are synced so if you drive 9mph over the speed limit you get ALL green lights for several miles. Weaving in and out of traffic is required for this which lowers the mpg some of course.
Now that theres less traffic the lights seem to have gotten out of sync. I think they're just not operating at rush-hour mode or something.
I have found myself caring less about the mpg number though with gas prices trending down!
 

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With my 2019 (Sept 2018) before the recent updates, it would fake shift harshly if over about 20% throttle. With the latest updates it seems more like 30-35% throttle and they shifts are much softer and definitely don't lurch as much.
Are you saying that your car will fake shifts with 30-35% throttle, but that it's at least smoother than before?

If that is the case, then I suspect there may be some software differences between model years. Ours will not fake shifts until throttle position is 50-60% or more. Below that, it'll rev the engine up to where it wants it to be, and hold it there as it varies the pulley ratios. (For reference, I'm basing throttle percentage on the digital throttle position indicator available on the dash-top display.)

The only exceptions to that are the first moderate load in the morning (where there's some rev surging that appears to be due to cold fluid temperatures, because it only happens during the first minute or so of load), and every now and again we'll feel a random impulse through the system. It doesn't happen often, it's not predictable, and it's only for a split second (so I've never been able to observe the tachometer while it happens). I'm not sure the tach would show anything anyway -- it feels more like the impulse you get when the A/C compressor engages...just more pronounced.

Ours is a 02/20 build with about 700 miles on it total. I'm guessing that any large swings in operation due to adaptive learning have taken place by now. Not that it stops trying to adapt to the driver, but that it's pretty much behaving now how it'll continue to behave forever.
 
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