2017 Subaru Forester 2.5 6M- rev hang?

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Ryan, my 2014 XV Crosstrek 5spd did the same thing with the high idle hang between gears or in neutral when rolling.

I believe with any E-throttle vehicle, automatic or manual, you'll find this high idle situation in neutral or between gears (depending on the trans) only when the vehicle is in motion. If no ground speed is detected, it will instantly idle down once warm.

Are you digging this 6spd overall? I still haven't driven my SILs.
 
The vehicle only has 800 miles on it so I haven't run it anywhere near redline but I love it overall. I think it will be a really good family car for us. Already got all the glass tinted with ceramic tint, installed a tow hitch, roof rail cross bars, and got some weathertech floor liners. I think I want to upgrade the speakers but that's about it. I plan on changing the trans and diff oil by about 10k miles. Figuring on redline fluids.
 
Previous gen foresters benefited greatly from a shifter bushing upgrade. I'd contact kartboy.com and see if one of thier existing kits will work. I put a kartboy shifter kit in the 09 forester, and it was a world of difference. Not sure how the factory shifter feels on the newer models, but I'd assume at this point Subaru re-used existing bushing designs that have been pretty standard for the last 20ish years for them.

I had the Cobb ssk in my LGT, and having both, I'd get the kartboy and be just as happy. The Cobb ssk was one of those absolutely beautiful parts to behold, but you never get to see it! And once it's set, the adjustable feature is kinda pointless. Kartboy figured that part out for you, so no point in any trial and error.
 
I remember that at least on my 2000 Maxima, rev hanging only happened at moderate revs. When really pushing it, I do not recall noticing it.
 
Originally Posted By: ryanschillinger
The vehicle only has 800 miles on it so I haven't run it anywhere near redline but I love it overall. I think it will be a really good family car for us. Already got all the glass tinted with ceramic tint, installed a tow hitch, roof rail cross bars, and got some weathertech floor liners. I think I want to upgrade the speakers but that's about it. I plan on changing the trans and diff oil by about 10k miles. Figuring on redline fluids.


Subaru Super-S is your friend!
 
Originally Posted By: ryanschillinger
Even our 2013 Corolla, with drive by wire, decelerates instantly when you let off the gas. Never had one do this.


Yes, my 2007 Corolla with 5MT also dropped revs predictably when shifting. It truly is just a function of how the powertrain engineers have decided to address tailpipe emissions (rather than throttle actuation type).

Here's my theory...and it took me about 10 seconds to come up with this, so it's worth what you paid for it...

Subaru probably have a relatively high take-rate on manual transmissions (at least compared with others in the industry). As a corporation, they may feel the need to program this type of emissions mitigation into the ECU programming because a relatively high percentage of their cars are ordered with manual transmissions. I would imagine that Toyota, on the converse, probably have one of the lowest take-rates of manual transmissions in the industry. Because this rev-hanging "feature" is beneficial (from an emissions standpoint) only on manual transmission-equipped vehicles, maybe Toyota have decided to focus efforts in other areas, and don't find the value in spending the R&D on something that would benefit only 2-3% of their vehicles.

I dunno...just a shot in the dark.
 
Originally Posted By: ryanschillinger
but I special ordered a manual transmission because I enjoy driving stick. This makes it less fun. Even our 2013 Corolla, with drive by wire, decelerates instantly when you let off the gas. Never had one do this.


Ordering a manual instead of an automatic is the best thing I've read on here in a long time. Cngratulations
smile.gif

Engine braking when you close the throttle is normal unless you have horrendous clutch slip.
 
Originally Posted By: 05LGTLtd
Previous gen foresters benefited greatly from a shifter bushing upgrade. I'd contact kartboy.com and see if one of thier existing kits will work. I put a kartboy shifter kit in the 09 forester, and it was a world of difference. Not sure how the factory shifter feels on the newer models, but I'd assume at this point Subaru re-used existing bushing designs that have been pretty standard for the last 20ish years for them.

I had the Cobb ssk in my LGT, and having both, I'd get the kartboy and be just as happy. The Cobb ssk was one of those absolutely beautiful parts to behold, but you never get to see it! And once it's set, the adjustable feature is kinda pointless. Kartboy figured that part out for you, so no point in any trial and error.


Upgraded shifter parts
laugh.gif
you used kartboy, I used JMR clubsport for my shifter mech. The improvement in ergonomics alone is worth more than gold, the increased accuracy and speed of gear selection is worth more than the improvement in ergonomics! After suspension/tyres/brakes&geometry an upgraded gear selection mech is a hugely enjoyable part of any vehicle.
 
Originally Posted By: Hokiefyd
Originally Posted By: SteveSRT8
I have seen older vehicles with a mechanical throttle body setup that uses an air bleed system to increase revs, and others that have a small electric motor to move the throttle a small amount when desired...


Yep; my '84 Cutlass with a computer-controlled Quadrajet would do it. It's not related to, or caused by, drive by wire throttle systems. It's an emissions mitigation technique that's enabled by the use of computer or vacuum control, and has been in place for decades.


I remember finding these back in the 70's (malaise era) when the emission controls were all vacuum / mechanical. You know, when a quadrajet had around 3 choke pull-off's, vacuum breaks, etc.... I remember a particular 1975 Ford Courier (Mazda) that would hang idle forever. I found this little device, and yes it was for emissions.

https://en.wikipedia.org/wiki/Dashpot
 
I drove a mid-80's or late 80's Escort that did that rev hang. Was annoying. Hadn't run into that until I got my 2011 Camry. If I drive it like I would drive any other stick, it results in "flare" of the rpms. The fix is to just get off throttle faster, like let off before I start to push the clutch. You can get used to it, or at least I have.

Just a pesky emissions things. Enjoy the car for what it is, perhaps one of the last manual trans cars. The handwriting is on the wall, even if we have a few more years.

Who knows, maybe someday someone will be able to map it out of the ECU.
 
Originally Posted By: supton

Who knows, maybe someday someone will be able to map it out of the ECU.


I think we're more likely to see manuals mapped out of existence.
 
Originally Posted By: dishdude
Originally Posted By: supton

Who knows, maybe someday someone will be able to map it out of the ECU.


I think we're more likely to see manuals mapped out of existence.


Oh I fully expect that. What I meant was for this Subaru model in particular--perhaps someone somewhere will reprogram the ECU for this. On my VW I had the ECU tuned to turn up boost and turn down the EGR. I don't know what has changed over the years in the ECU, I'm sure its getting harder to adjust, but perhaps the rev-hang is something that can be fixed with a tune.
 
A few things I wanted to address from the above posts.

This car doesnt come with subaru extra S, it comes with subaru extra MT a 75w80 gl-5.
I have tried a few different gear oils and
the best was motul gear 300, redline 75w90NS was good too.
you will lose some really cold shifting performance .. think 20F just started car.
otherwise feels similar to better than stock.

Its a good idea to change the first time early. Mine came out silver and nasty.

After that even with severe service 30000miles is a good number.

You will need aprox 4qt for transmission and rear diff.
motul comes in liters so 4 is plenty.

Very easy to do.. not sure if the new ones are hex

my 2015 is t70 on the MT, and I use a torque stick on the rear diff plugs
The torque stick is very squared off 1/2" drive and fits the 13mm square better than my 13mm square adapter(from drain plug kit)
https://www.amazon.com/Motul-Gear-Fully-...HY025HEAA65SS0R

First time can be a bear.. I remember unfondly basically hanging from a breaker bar and the drain plugs not moving.
I used my dewalt impact on them .. which is not advisable but I had a big springy torque stick and it was either that or try to hammer upwards on a breaker bar with 12" of ground clearance and a surgically repaired wrist.

The impact worked fine just went at it easy. remember its a steel plug in an alum case.. bad things can happen if you arent careful.
 
Rand thanks for that info! It never gets to 20 here but I do travel to the mountains occasionally. Always liked redline but wouldn't mind trying mogul if it's better.
JTK I'm not sure. I don't think it has a dipstick. I honestly can't think of any stick vehicles I've owned that had one. Maybe I'll take a closer look. Been monitoring the engine oil dipstick but I'm over 1000 miles now and doesn't seem to have used any.
 
Originally Posted By: ryanschillinger
I'm not sure. I don't think it has a dipstick. I honestly can't think of any stick vehicles I've owned that had one. Maybe I'll take a closer look. Been monitoring the engine oil dipstick but I'm over 1000 miles now and doesn't seem to have used any.


The 6spd may not. The 5spd on my XV Crosstrek did have a dipstick and drain plug.
 
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