nipper Posted August 1, 2011 Share Posted August 1, 2011 I may have found one. It may not (if it works) stop the downshift into 3rd, but it will soften it. I found this by accident. The reason it may work is because the TCU learns how you drive. You will be teaching it a softer way of shirting making it think you have a lighter right foot. Remove the + cable for a five minutes, this will clear the ECU and TCU memories. Put the cable back on and drive the car with a SOFT right foot. From any stop take about ten seconds to reach 30 mph. When coming up to a stop sign or red light coast to the light. Do not drive up to it and brake at the last minute. Do a couple of these at 40 mph, 13-15 seconds to get up to speed. Then do one that takes 25 seconds to get up to 55-60. Do this for about 8 miles. During this you may get one late shift, just back off on the gas, the computer is trying to figure out how you drive. What does this do? It teaches (lies) to the puter that when you need to accelerate for a hill, you are not one to bury the gas when accelerating. What I discovered now is that when going up a will, instead of an immediate 4-3 downshift. it does a 4 - 3 1/2 (unlocks torque converter) then will go to 3 after a second or so. This is generally better for the engine and drivability (read your nerves). I do not know How it effects down hill as I kept having some idiot or another infront of me piddling along at 50 on a 65. It may be my imagination but it seems to have also affected deceleration, making it stronger on the coast. But then again I just had my exhaust system repaired so it may just be me, but I think it did. May work may not but the logic does make sense. Quote Link to comment Share on other sites More sharing options...
bheinen74 Posted August 1, 2011 Share Posted August 1, 2011 (edited) could be good info. But whenever you reset the computer by unhooking the battery, it just throw it into learn mode = menas for 3-4 gas tanks your mileage suffers dramatically 18mpg for a while while it figures (or tries to figure) out how to maximize the maf and tps etc....based on how the throttle is opening and closing. Just wait til microsuks is in all our future cars.. I am not sure you are going to see the affects after it has learned it may go back to how it was programmed to handle cruise.... In learning mode, it is not able to pull timing quickly, and that really may be all you are seeing..when it is able to pull timing, it will downshift more abruptly... Edited August 1, 2011 by bheinen74 Quote Link to comment Share on other sites More sharing options...
nipper Posted August 1, 2011 Author Share Posted August 1, 2011 No. The car figures it out in the first 8 miles as you may drive the car (leadfoot) then your wife (leader foot) then a kid (light foot) or any mix inbetween. Each time the driver changes the car has to learn the new driver and aparently it does it in the first 5-8 miles. The hard reset clears it back to a baseline and it will adjust from there. It also proves on another level if you want to start driving for MPG it helps to reset the TCU and drive in the new pattern. http://www.cobbforums.com/forums/showthread.php?30700-Adaptice-learning-4EAT-TCU http://www.fitfreak.net/forums/general-fit-talk/62010-how-does-ecu-adapt-car-driver-2.html O can post more but they all work basically the same way. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted August 1, 2011 Share Posted August 1, 2011 weird, i've done a hundred "resets" and swapped EJ25/EJ22 ECU's and TCU's and never noticed a difference. i'm not very discerning though, but shifting is rather obvious in the mountains here. what is annoying is how i can carry a mountain grade without downshifting if i'm using the pedal, but if i'm using cruise it downshifts....anyway to prevent that? i'd be happier than a two tongued dog if i could keep it from needlessly downshifting all the time. Quote Link to comment Share on other sites More sharing options...
nipper Posted August 1, 2011 Author Share Posted August 1, 2011 weird, i've done a hundred "resets" and swapped EJ25/EJ22 ECU's and TCU's and never noticed a difference. i'm not very discerning though, but shifting is rather obvious in the mountains here. what is annoying is how i can carry a mountain grade without downshifting if i'm using the pedal, but if i'm using cruise it downshifts....anyway to prevent that? i'd be happier than a two tongued dog if i could keep it from needlessly downshifting all the time. Rolling hills (mountains) leave it in D3, but technically you arent supposed to use cruise on frequent up and down hills. Japanese cruise is geared towards this I have no idea why, Its not just subaru. Quote Link to comment Share on other sites More sharing options...
bheinen74 Posted August 1, 2011 Share Posted August 1, 2011 I could drive 750 miles straight to Colorado not using cruise and never have it downshift to a 3rd gear not even once, all keeping a perfect steady speed using my foot. Using Cruise, well it was constantly searching like 10-15 times on hills, and coming out of TC lock up etc... silly puters. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted August 1, 2011 Share Posted August 1, 2011 odd for a car that is quite popular in mountainous regions, seems after a few decades they might figure that out? has anyone attempted anything to mitigate that or just unfeasible because of gearing? gas mileage in D3 is not what it is when i use my foot in 4th. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted August 1, 2011 Share Posted August 1, 2011 oh and to stay slightly on topic...sorry nip!!!....has yours always done this or has it gotten worse or anything? there's a shift resistor and while i would expect it would throw a code if it wasn't working maybe it could degrade or another model might shift better? XT6's are the opposite, a sort of delayed shifting between 3rd and 4th, so i actually unplug them to firm it up. in the SVX community i believe they make some device to firm up shifts...seems like it shouldn't be too hard (or already done) to go the opposite way with it? Quote Link to comment Share on other sites More sharing options...
nipper Posted August 1, 2011 Author Share Posted August 1, 2011 NO code resitor is fine and has always done this. Even the 98 did the same thing, and that was a 2.2 legacy. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted August 1, 2011 Share Posted August 1, 2011 have you ever seen that SVX mod/controller for the shift resistor, it played with firmness of shifts as well. there was a company making that at one point. Quote Link to comment Share on other sites More sharing options...
CNY_Dave Posted August 1, 2011 Share Posted August 1, 2011 I may have found one. It may not (if it works) stop the downshift into 3rd, but it will soften it. I found this by accident. The reason it may work is because the TCU learns how you drive. You will be teaching it a softer way of shirting making it think you have a lighter right foot. Remove the + cable for a five minutes, this will clear the ECU and TCU memories. Put the cable back on and drive the car with a SOFT right foot. From any stop take about ten seconds to reach 30 mph. When coming up to a stop sign or red light coast to the light. Do not drive up to it and brake at the last minute. Do a couple of these at 40 mph, 13-15 seconds to get up to speed. Then do one that takes 25 seconds to get up to 55-60. Do this for about 8 miles. During this you may get one late shift, just back off on the gas, the computer is trying to figure out how you drive. What does this do? It teaches (lies) to the puter that when you need to accelerate for a hill, you are not one to bury the gas when accelerating. What I discovered now is that when going up a will, instead of an immediate 4-3 downshift. it does a 4 - 3 1/2 (unlocks torque converter) then will go to 3 after a second or so. This is generally better for the engine and drivability (read your nerves). I do not know How it effects down hill as I kept having some idiot or another infront of me piddling along at 50 on a 65. It may be my imagination but it seems to have also affected deceleration, making it stronger on the coast. But then again I just had my exhaust system repaired so it may just be me, but I think it did. May work may not but the logic does make sense. A downshift where it doesn't really need to, so it revs quite a bit, or a bit of flare and a big BANG when it drops into 3? Dave Quote Link to comment Share on other sites More sharing options...
idosubaru Posted August 1, 2011 Share Posted August 1, 2011 a bit of flare and a big BANG when it drops into 3? Dave i've seen that before dave, please tell me what that is. TPS? Quote Link to comment Share on other sites More sharing options...
bheinen74 Posted August 1, 2011 Share Posted August 1, 2011 have you ever seen that SVX mod/controller for the shift resistor, it played with firmness of shifts as well. there was a company making that at one point. SVX "Crush Mod" is what they term it. But if you have a flare, maybe the brake band or whatever it is called is slight need of adjust. Quote Link to comment Share on other sites More sharing options...
nipper Posted August 2, 2011 Author Share Posted August 2, 2011 have you ever seen that SVX mod/controller for the shift resistor, it played with firmness of shifts as well. there was a company making that at one point. That is the resistors purpose to soften up the shift a bit Quote Link to comment Share on other sites More sharing options...
eulogious Posted August 2, 2011 Share Posted August 2, 2011 (edited) The reason the TCU will shift differently when in cruise is because it uses different shift maps for cruise. The TCU has a cruise input to tell it when the cruise control is on, and when it is on, it uses different shift maps for "better economy". That's the reason for up-shifting more frequently when in cruise. This is with factory cruise of course. Dealer/aftermarket systems are different of course. So with that being said, you could probably just clip that wire going form the cruise to the TCU, and it would never activate those shift maps because it would never know when the cruise is on. Don't think this will throw a code either, but I am not sure on that one. That would solve the "weird shift issues" while using cruise. Well, it at least lets you use the non-economy shift maps, which may or may not be better... I am also fairly certain that the TCU DOES NOT learn anything, at least not in the early years (ODB1?). It's not in the code to learn, and there really isn't any space to store it either. I am 95% positive on this, since I did spend several hours/days going over the disassembled code when modding my TCU. It was hard to find space to store the new code that was added to my modded one! I can tell you for a fact that no matter how long my TCU is unplugged it acts the same way it did before I unplugged it. I have spent hours troubleshooting different TCU's while driving around with them plugged in, removing my modded one and what not, and there has never been any difference in the way the car acted when using different tcus, at least when using them in the "stock" form. This was true on my loyale as well, not just my legacy. In stock form, both the TCU from my legacy and loyale shifted and acted the same way. Any "learning" that's done is all done by the ECU, which does affect the way the TCU operates. My guess is that once the ECU learns the different driving style, it sends different signals to the TCU (probably more like different timing of the signals, not different signals...) which will cause it to operate in a different way. Edited August 2, 2011 by eulogious Quote Link to comment Share on other sites More sharing options...
CNY_Dave Posted August 3, 2011 Share Posted August 3, 2011 i've seen that before dave, please tell me what that is. TPS? TPS doesn't fix it, but resetting the computer fixes it for at least a month. Seems to be an H6 thing. Dave Quote Link to comment Share on other sites More sharing options...
nipper Posted August 3, 2011 Author Share Posted August 3, 2011 Finally let see if this sticks. I need to find that blu wire and cut it and see what happens. I wonder where is the easiest and best place to do a little surgery Quote Link to comment Share on other sites More sharing options...
subsince77 Posted August 4, 2011 Share Posted August 4, 2011 Sure would be nice to have some control over that. I don't use cruise on the passes of course, but just about anywhere around here you are running through some hills, some steep. That thing wil run itself up to 6000 rpm in an instant when it could have done fine in the next gear. Wakes you right up! It does it pretty smoothly though - no banging into gear. In my opinion, it needs another gear. 4 just spreads them out oo much. I know there is a newer one now, but that's 10 years away for me. Quote Link to comment Share on other sites More sharing options...
eulogious Posted August 4, 2011 Share Posted August 4, 2011 Finally let see if this sticks. I need to find that blu wire and cut it and see what happens. I wonder where is the easiest and best place to do a little surgery Are you asking what wire to cut, ? Or just making a comment, I can't really tell Quote Link to comment Share on other sites More sharing options...
spazomatic Posted August 4, 2011 Share Posted August 4, 2011 what I do is anticipate when the car's gonna want to downshift. before I get to the incline, I'll get on the gas a bit, and then feather it back as I ascend, so that by the time I reach the top, I'm back down to my cruise speed, and it didn't have to downshift. kindof defeats the purpose of driving in cruise I guess, but it works well for the occasional undulating road (like say, going from pueblo to castle rock on I-25) if I'm on a road where it's constantly shifting around, I'll pull it into 3rd and just leave it. Quote Link to comment Share on other sites More sharing options...
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