Auto Vs Manual

Dedman said:
a power button which seems to do nothing.
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The power button changes the shift pattern i.e. more "sporty". I usually have the power switch on.

From memory I may have stalled once on a steep climb but generally the auto will just lug up a steep climb. I do tend to use it like a manual and select my gear before a climb and activate the pseudo centre diff lock switch of course!
 
The tech specs document as published by SUBARU (AUST) PTY LIMITED for the "second generation Forester" P-FTB03 auto trans states:

"Power: mode is selected by depressing a switch on the gear shift lever console. This causes gear shift to occur at a higher vehicle speed than normal mode and allows a lower gear to be held longer thereby improving acceleration."

and

Peak power and torque outputs of the 2.5-litre Boxer engine occurs at relatively low engine speed of 5600 rpm and 3600 rpm respectively.
The emphasis of the ongoing development has centred on improving the mid-range operating conditions to maximise responsiveness and part throttle torque delivery. Torque delivery starts from 183.4 Nm at @ 1200 rpm, reaching a peak of 223 Nm at 3600 rpm and still maintaining 191 Nm at 5600 rpm.
 
I have no idea how to tell if the computer is intervening but I can tell you that my SH has no such problem. I just got back from testing it on a steep slope. I should have taken photos but I always forget to do that.

Slope was 24%
Surface, clean, dry bitumen (hot mix)
Weather sunny about 12 degrees C
I am running 215X70X16 Toyo Open Country AT 2 with only a few thousand Ks on them so diameter is about 23mm greater than OEM

I stopped on the steepest part of the slope, switched off traction control which leaves VDC engaged, selected manual mode 1st gear on the transmission and floored it. The front wheels slipped about a half rotation then it accelerated up to about 4000 rpm within about 25 metres.

I also tested the stall speed because I think I was a bit tentative when I first tested it and found that it is actually 2500 rpm.

Would it be worthwhile taking it to a tuning specialist or put it on a dyno to see what is happening?
 
Kevin said:
The tech specs document as published by SUBARU (AUST) PTY LIMITED for the "second generation Forester" P-FTB03 auto trans states:

"Power: mode is selected by depressing a switch on the gear shift lever console. This causes gear shift to occur at a higher vehicle speed than normal mode and allows a lower gear to be held longer thereby improving acceleration."

and

Peak power and torque outputs of the 2.5-litre Boxer engine occurs at relatively low engine speed of 5600 rpm and 3600 rpm respectively.
The emphasis of the ongoing development has centred on improving the mid-range operating conditions to maximise responsiveness and part throttle torque delivery. Torque delivery starts from 183.4 Nm at @ 1200 rpm, reaching a peak of 223 Nm at 3600 rpm and still maintaining 191 Nm at 5600 rpm.
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The figures I quoted were from a dyno readout done in the US and put up on the forester owners forum so it represents torque at the wheels rather than theoretical engine torque. I didn't reference it because you have to be a member to access it and I don't know if other contributors are members. It was also lacking a legend so I'm not sure what units the measurements were in.
 
Kevin said:
"Power: mode is selected by depressing a switch on the gear shift lever console. This causes gear shift to occur at a higher vehicle speed than normal mode and allows a lower gear to be held longer thereby improving acceleration."
Click to expand...
What I though. So it will do nothing when flooring it in 1st gear only.

Kevin said:
Peak power and torque outputs of the 2.5-litre Boxer engine occurs at relatively low engine speed of 5600 rpm and 3600 rpm respectively.
The emphasis of the ongoing development has centred on improving the mid-range operating conditions to maximise responsiveness and part throttle torque delivery. Torque delivery starts from 183.4 Nm at @ 1200 rpm, reaching a peak of 223 Nm at 3600 rpm and still maintaining 191 Nm at 5600 rpm.
Click to expand...
Yep so torque at 1200 rpm is better than the peak torque of my old EJ20...
 
Beachworm said:
Slope was 24%
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14 degrees isn't an overly steep slope. I would expect similar performance to what you have listed from my car. Try do that slope with a brick in front of each wheel. Will it climb over them or sit there doing nothing. I suspect mine would sit there doing nothing.
 
Dedman said:
14 degrees isn't an overly steep slope. I would expect similar performance to what you have listed from my car. Try do that slope with a brick in front of each wheel. Will it climb over them or sit there doing nothing. I suspect mine would sit there doing nothing.
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I was thinking the same when I got to it this morning but it's the steepest slope I can access without driving 100K or more to the bush. I can't really put bricks on the road as it would interfere with traffic and I don't have any bricks anyway. Sorry I can't help more.
 
Yes, that is steep - but it is also an XT
 
Really? How can you tell? I didn't notice a bonnet scoop.
 
[MENTION=4168]Dedman[/MENTION] I have a ECU out of my parts car (2006 SG Auto XS, and/or matching Transmission ECU) if you want to swap them out and see if it is that causing your issue
 
^ That's a nice offer SS!

Beachworm said:
Really? How can you tell? I didn't notice a bonnet scoop.
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Says "XT" on the tailgate and also if you check the drop-down detail it also says "XT". I think they dropped the scoop on later model XTs.
 
I zoomed in and saw that straight after I posted - edited my post but the edit doesn't show up. That's what I get for watching videos in small format.
 
Kevin’s car is a series 1 SG and Alex’s is series 2, so different engines and who knows what else. I don’t have much info or experience with dbw problem solving, so I don’t know how you tell what the throttle is actually doing. If it runs some form of potentiometer you might be able to get a voltage reading. That’s how a TPS works, maybe the same for DBW. I’d be interested to know just what the differences are in different situations between input and actual.

Meanwhile, a service commemorating the passing of the throttle cable will be held later this month. Despite advancing years, our good friend still provided loyal service, and could always be relied to pass on all messages from us to our engines. His fall from grace was not of his own making. His true worth can be measured by the weak, inconsistent performances of his rather lacklustre replacement. There will always be a place in my cars for you. RIP
 
with RomRaider you can view and log the accelerator pedal position vs. Throttle Position sensor,
it will give you the answer to that question at least.
 
izigwalker said:
with RomRaider you can view and log the accelerator pedal position vs. Throttle Position sensor,
it will give you the answer to that question at least.
Click to expand...

Good to know. I’d be fascinated to see the results
 
Well I tried and failed. Not sure if the signals are not there or if the ****ty version of OBDII software I was using is just rubbish. Anyway I only had an absolute throttle position signal which never went above 80% but then I also have a vehicle speed that never went above 60km/h despite doing 100. Not a lot of faith in the results thus far.
 
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Have you tried resetting the ECU Maps via disconnecting the battery etc? Previous owner might have driven like a Grandma, so the maps are all tuned to that style of driving?
 
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^ my thoughts too Squires!
[MENTION=44]Rally[/MENTION], pissa mate! I love a cable too even though I've not driven anything with dbw.

Dedman, have you done a transmission service? Might be time for new fluid and filter?

If it's a TCU issue you should be able to reconfigure this to do what you want it to do. Just need to find someone who can reprogram it. I'm sure it's possible.

Cheers

Bennie
 
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