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Discussion Starter #1
So I test drove a 2010 Forester yesterday, and liked everything about the car other than its acceleration. When pulling out in traffic and flooring the accelerator to merge, there was a noticeable delay before the engine revved up and the car began to take off. Is this normal for the Forester? I understand it only has an H4 that puts out 170, so it won't pickup at the same rate as my 300m does, but it wasn't so much the rate as it was the 2-3 second delay before anything started happening. I would think this could get dangerous merging on the interstate in relatively high traffic conditions. Is this the effect people are hoping a new CVT may fix? Thanks for any input.
 

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2010 Forester 2.5X Premiu
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To me the CVT in the Outback seemed to lag more.

I traded a 225 hp Acura for the Forester. I just adjusted my expectations as regards acceleration. I find it responsive enough for me, but I'm not 26 any more.
 

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2004 Forester XT Premium 4EAT
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So I test drove a 2010 Forester yesterday, and liked everything about the car other than its acceleration. When pulling out in traffic and flooring the accelerator to merge, there was a noticeable delay before the engine revved up and the car began to take off. Is this normal for the Forester? I understand it only has an H4 that puts out 170, so it won't pickup at the same rate as my 300m does, but it wasn't so much the rate as it was the 2-3 second delay before anything started happening. I would think this could get dangerous merging on the interstate in relatively high traffic conditions. Is this the effect people are hoping a new CVT may fix? Thanks for any input.
There have been numerous discussions here over the years in regards to the 4EAT delay when flooring the pedal. The general consensus is that the ECU/TCU doesn't respond well to the sudden "pedal to the metal" input, and that better results are usually had by either tapping the accelerator once before going full throttle from a stop, or "rolling" onto the pedal. It's a quirk that most every 4EAT owner here is familiar with... it just takes a little getting used to and learning how to work around it.
 

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2016 Forester XT AT
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I agree with Silke, a more "gentle" approach seems to work well, it has even caught me by surprise at how well it will accelerate once you know how to do it.

Also, it will take some time for the computer to learn your driving style, so on a test drive of a new one the computer will be a little confused.
 

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2010 Forester
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Interesting... My wife and I didn't know anything about this throttle manipulation when we test drove the non XT model. Despite what seemed like a slight hesitation, my wife loved everything about the Forester and still wanted to buy it. I talked her out of that silly notion, and convinced her that she needed the XT. :biggrin:
 

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2010 Forester XSE, PZEV
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From my experience test driving an Outback with CVT, there is a noticeable lag/delay with the CVT, and none with our 4EAT Forester. The Forester has plenty of zip when accelerating, and I have to be careful when I am parking it. It is an incredibly FUN car to drive! :icon_cool:

We thought about waiting to see if the next Foresters would get the CVT, but the CVTs seem to be having some issues already.
 

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Discussion Starter #7
Thanks for the input. I will have to go back to the dealer and try one out again playing with some different pedal manipulations to see what it could do. Do you think they program the car to respond that way for better fuel economy? Loved the rest of the car, still thinking I will end up with one. Was truly amazed at how well it could handle, and the small turning radius. Really impressive for a car with nearly 9 inches of ground clearance.
 

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2010 Forester Sport-Tech
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169 Posts
Yup, turning radius is incredible. I'm also coming from an '04 Sentra SE-R which can't turn for beans in a parking lot.
General handling is great! We also test drove a Santa Fe Sport and an Outlander XLS. The Outlander didn't wow us (nothing was "wrong" with it, just didn't "Wow" us) and the Santa Fe felt big and soft. We both preferred the Forester's handling and general feel which is why we bought one.

As far as throttle response goes, I haven't noticed any lag, but I am babying my new Foz. The XT had much more "Go!" but at an extra $100 per month for 5 years, my wife vetoed it. Maybe our next Fozzie will be an XT.
 

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2018 ForesterXT Touring..
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E^vol, that's what I like to hear. You've only had your Forester for 2 weeks or so, and you're talking about your next one(XT). Once the Subaru bug bites ya, it's got you good:).
 

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2016 Forester XT AT
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Thanks for the input. I will have to go back to the dealer and try one out again playing with some different pedal manipulations to see what it could do. Do you think they program the car to respond that way for better fuel economy? ...
Try the sport shift mode and the manual mode too (get the salesman to show you them). The auto trannie is very versatile.
 

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2016 Outback and WRX CVT
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My thinking is along the lines of pleiad7's.

Although I've found that the "Sport" mode is more to my liking (holding gears longer, etc.), I find the manual mode somewhat lacking in terms of both upshifts and downshifts, nevertheless, the latter does bring a bit more driver involvement into the equation, and can help you better react to some situations.

I've always been a "stick-man," and although I'm still far from perfect at it, it does give me immense joy to row through the gears. As a result, earlier on in my life, I typically don't find myself enjoying the drive as much, when in a slushbox-equipped vehicle. As the years have passed, though, I've started to realize that this is my fault - not that of the vehicles - and that there can be just as much fun to be had by trying to "plan ahead" and to think of ways to make the vehicle's ECU and TCU do what I want it to do: to play little tricks on it. And while this may never be the joyous occasion as hitting a great heel-and-toe, for I'm essentially working "against" the machine, it is, nevertheless, quite fun. :wink:

Also, it will take some time for the computer to learn your driving style, so on a test drive of a new one the computer will be a little confused.
^ The ECU/TCU does not learn any "driving behavior." All "learning" is based against knock (or perceived knock). The vehicle actively tries to optimize its power delivery, while ensuring that the engine's operating parameters are "safe," and that is the extent of the learning.

Even if you persistently buried the pedal, the vehicle will still be dog-slow, if it has determined that the engine is knocking or on the verge of doing so. The vehicle does not "learn that you like to drive fast" and alter its behavior to-suit.

And while it is possible to reprogram throttle-mapping either via the ECU or via an external aftermarket device that interfaces with the DWB unit (or, for that matter, with something like the Si-Drive setup), that again has no effect, quantitatively, on how "fast" the vehicle will be - it will still reach its acceleration marks in the same quantitative window, rather, it will simply "feel faster" as the throttle opening angle can be incremented/scaled beyond what is more typical (i.e. a 10% depression of the throttle can be scaled to produce a "WOT" scenario). Furthermore, this remapping is not actively "learned" by the car, but rather, resides within lines of code inside the ECU, and will not change unless modified by one of the aforementioned means.

The one caveat I'll put on that is that's with regard to the traditional transmission - I have no idea how the CVT's TCU "sees" things. :smile:
 

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I believe there was one person on here not that long ago where they had a slow response issue (no codes) and had to get a new throttle control which fixed things. Might want to look into that. I have no idea how to check.
 

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2016 Outback and WRX CVT
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^ That's a good question - if you're able to pull the base ROM off the ECU and then look at throttle mapping/"Requested Torque," I *suppose* that some datalogging combined with a bit of math via a spreadsheet would reveal discrepancies in throttle mapping versus throttle input, but I truly don't know if that would work well.

I'd imagine that any fault within the DWB system would be able to be diagnosed via traditional electronics diagnosis means (multimeter)?

To go with such a conclusion so early, though, might not benefit phillyguy, as he is test-driving/pre-purchase. I wonder maybe if he should either test more examples (to be sure that the one he started with didn't have some hidden issues) or, alternatively, if he can bring along a friend who is well-versed with Subarus, so that they can determine if what they're feeling is out-of-norms?
 

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^ That's a good question - if you're able to pull the base ROM off the ECU and then look at throttle mapping/"Requested Torque," I *suppose* that some datalogging combined with a bit of math via a spreadsheet would reveal discrepancies in throttle mapping versus throttle input, but I truly don't know if that would work well.

I'd imagine that any fault within the DWB system would be able to be diagnosed via traditional electronics diagnosis means (multimeter)?

To go with such a conclusion so early, though, might not benefit phillyguy, as he is test-driving/pre-purchase. I wonder maybe if he should either test more examples (to be sure that the one he started with didn't have some hidden issues) or, alternatively, if he can bring along a friend who is well-versed with Subarus, so that they can determine if what they're feeling is out-of-norms?
^ good points and good suggestions.

I think we will agree to disagree on the trannie learning your driving thing. My comments were based on what the dealers service rep told me, as they re-set the ECU at the 48,000 km service and he warned me I may note some differences but within 1,000 kms it will re-learn my driving style. Also, the salesman noted to me during the test drive that I should not be too gentle as the trannie will "learn" that style and cause issues later. The dealer (they have a high % of retirees, ie gentle drivers) has to re-set the computer on almost every Subaru trade-in to make them respond as they should. So all just hearsay from the dealer on my part.
 

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^ Don't believe the dealership. :smile: :wink:

OK, I don't mean it as bad as it sounds. Rather, just don't take their words at face-value. Instead, seek to confirm what they may rattle off at the tips of their tongue with information that can be confirmed. This is a very good example, actually, of such.

What I quoted of the vehicle "learning" is knowledge and know-how derived directly from our fellow enthusiasts and hobbyists who've delved into the lines of code within the ECU. What I've said about the ECU's "learning" occurring against knock events is the plain truth, and is seen in countless threads in the OpenSource tuning community as well as within various Subaru-enthusiast Forums. Here's a good internal reference, with pertinent outlinks:

http://www.subaruforester.org/vbulletin/f95/whats-scoop-ecu-learning-driving-habits-64422/

In terms of TCU "learning," that is truly a mystery for the time being...while some have said that they can observe a subjective difference in the vehicle's shifting behavior - akin to the difference between sticking the gearshift into "Sport" mode versus the standard "Drive," I have never seen anything even remotely quantitative or more objective regarding this matter.

So far, there has been some attempt at TCU reverse-engineering, but it's still in the early stages:

http://legacygt.com/forums/showthread.php/5eat-tcu-reverse-engineering-136175.html

While it is certainly possible that a certain manner of driving - i.e. aggressive delta of the throttle, use of the "manual mode" to hold gears (or even more use of manual or "Sport" modes, period), higher speed differentials, etc. - could certainly trigger a simple subroutine which would cause the TCU to, say, revert to "Sport" mode behavior, even if left in "Drive," such behavior of the vehicle has not yet been confirmed in a truly quantitative manner: all that's said is that "it feels like" or "it seems like," all subjective.

Again, it's not to say that it's impossible for the TCU to learn - rather, just that it hasn't been confirmed, either way: that it has not been confirmed that it is indeed how it learns, what it learns, or if it learns.

In going back to the ECU, however, what the dealership said to you is wrong, plain and simple, and this is not a matter of "he-said versus she-said," but is what we've proven in our collective community via actual access to ECU mapping:

After a reset - including having pulled the battery or a loss of battery power to the ECU - or a reflash, the ECU will revert to a "base" mode, with less-aggressive timing advance parameters. Also, during that time, it will re-learn many things, including idle, and the comments given by your dealership's service department is typically to qualm your (and other customers too, of course! :smile:) fears when and if the idle suddenly dips or the car even fails to pick up idle and dies, during those initial miles. Additionally, since the ECU will not restore full timing advance until it's reached its programmed criteria set-forth to do so, the car will also feel more sluggish than normal (why do people sometimes say that their car feels "stronger" after an ECU reset, then? it's because there was something already awry, and that the car was running at a lesser level in order to save itself; the ECU reset caused the car to artificially forget that such problems exist, and it runs harder, as-if nothing was wrong, until it again encounters the same problems), which may again concern those who are more observant/sensitive to the state of their cars - thus, those statements again aim to qualm such concerns.

The 1,000 kilometer quote is itself an overly conservative estimate of how long it takes for the car - if it is truly healthy mechanically and is fed quality fuel - to regain its full performance potential via the ECU "relearning" that all's well. To see just how much that's so, search the terms "Vishnu Reset" in a larger Subaru-enthusiast community, and you'll see how such a "reset" can artificially, but most rapidly, be brought to-bear. Typically, even without such heavy-handed interventions, the car will regain its full composure, including idle, after but a few tens of miles and one or two re-starts.

Whether you drive like a complete bat out of hell or whether you drive like a proverbial "grandma" has no impact on what the ECU does. It's mission is to deliver to the driver as much available power as often as possible - the "learning" that it does is to help it survive that mission, to steer it away from killer knock. [ To a certain extent, this is why "Map Switching" as well as "Real-Time" overlays are so highly sought-after features for many tuners or drivers who compete in motorsports events in their otherwise daily-driver vehicles. It allows the vehicle to utilize a more conservative - hopefully "safer" in terms of its knock characteristics - map during the daily driving, and to then, at the flip of a switch or the press of a few keys, change to a more aggressive mapping, to be able to push on the racetrack, drag-strip, or between AutoX cones. It's the mapping of the vehicle that changes its inherent behavior, not how you drive it. ]

Overall, be weary of your dealership.

Their advice per the above makes me think that they're either less technically inclined than they should be or, alternatively, that they are not willing to disclose such information to "the average customer," which is something that I detest - dealerships should not assume that we're all dumb, technically incompetent, or do not wish to learn advanced tech.

Furthermore, their ECU reset on vehicles at-trade-in may be completely innocent, but it can also do well to hide/mask, at least temporarily, some of the more common "hickups" that may affect our vehicles (i.e. look at how an ECU reset can get rid of the "stutter/studder/hesitation" that plague so many), and which, while not severe nor mechanically dangerous, can definitely still affect someone's buying decision, should they manifest.
 

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I noticed this in my test drive this week, too. For me, I assumed it because I'm very accustomed to my 12yo Corolla's behaviors. :) It was actually a problem on almost all my test drives, but most noticeable on the VW Jetta Sportwagen TDI.

By the end of the Forester testdrive, I was doing better and not an issue. I'm definitely going to test drive again with the advice given in this thread...
 

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Try out the car in sportshift mode... shifting gears on your own will help... I feel as though the engine is more responsive. Whamming the gas on the NA Fozzies does nothing.... You have to ease in to it.
 

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2016 Outback and WRX CVT
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^ AzN, I know your SH is rather modified, and that you're continue to look for more....

I'm not as gun-ho about modifying our SH, as it is the wifey's, and she is decidedly anti-modding :lol: :redface: - but has anyone in the SH community, both N/A as well as force-induced, tried messing with the throttle mapping, either by modifying the ECU's indwelling parameters:

http://legacygt.com/forums/showthread.php?t=123112&highlight=requested+torque

....or via the use of an aftermarket add-on device such as this:

http://legacygt.com/forums/showthread.php/official-test-ntd-throttle-control-unit-123112.html?t=123112&highlight=requested+torque

?
 

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Have you tried an XT? The power in those are very nice. My wife had a 2008 WRX and she test drove a regular Forester X because she figured better fuel economy and less money, she HATED it.... well loved the car hated the power. Went back and got out an XT and she was grinning from ear to ear. Much better power and feel to the car. Also I believe the suspension may be better, I could be wrong.
 

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^ My wife came to the '09 FXT from an '05 WRX (4EAT) - given the extra half-liter's displacement, you can imagine how much better the slushbox took to the FXT than it did to the WRX. :smile:

Strangely enough, we didn't feel the need for the turbo until we stepped-up our test-drive route to include higher-speed areas ( > 35 MPH speed limit). At that time, then became obvious to us that we needed to get the turbo.

Still, I do find the throttle mapping to be a little lacking. Not bad, but not great - but with the natural tendency for turbo vehicles to be a bit sluggish in terms of throttle-response when off-boost, the bad parts tend to get exaggerated.
 
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