Muppit Posted June 13, 2005 Share Posted June 13, 2005 Hey all, wikkid site you've got here, glad I discovered it Apologies if this has already been covered, I did search....pretty well... I have a 2.0 ltr 92 legacy, auto, which has just recently become front wheel drive. I think this because the front wheels slip at intersections, on the gravel etc whereas they never used to before. If i had intended for this to happen I'd be happy, but I haven't changed anything. I have been meaning to install the FWD fuse for a while now to try get it it more economical, so there's definately no FWD fuse in the FWD fuse slot, and no smoke or metal filings are coming from anywhere, is there a common cause for this? Appreciate any feedback, muppit Quote Link to comment Share on other sites More sharing options...
Andyjo Posted June 13, 2005 Share Posted June 13, 2005 i don't know why it would happen, but by putting in a fuse and driving around you'll burn out your tranny solenoid, and that's no good. From what i've read it's for dyno testing or something, not for driving around... if somehow that fuse got shorted... you might be in trouble with that... hopefully you want to keep it in FWD for a while Quote Link to comment Share on other sites More sharing options...
TheBigJ Posted June 13, 2005 Share Posted June 13, 2005 I'm pretty sure thats a 2.2l, not a 2.0. As for the problem you are having... try doing a search for "torque bind." There are several threads on that and it might give you some more information about your car, if not explain what is happening to it right now. I recommend going to a gravel parking lot with an assistant to see if you are REALLY not getting any power to the rear wheels Quote Link to comment Share on other sites More sharing options...
Flowmastered87GL Posted June 13, 2005 Share Posted June 13, 2005 Looks like the car is in New Zealand... most likely a 2.0 Quote Link to comment Share on other sites More sharing options...
Muppit Posted June 13, 2005 Author Share Posted June 13, 2005 Cheers for the replies, Yeah it's a New Zealand car, so 2.0l. I layed a mild pad in the old mans (gravel) driveway couple days ago testing it out, and like me, he's pretty sure it's FWD only. Being a nanna's car I think it'd have trouble 'lighting up' all wheels on solid ice, so to do a skid was pretty exciting for me As for the fuse issue, so far I've been reading a lot of contradicting opinions on this, but it seems to be that many people have installed switches thru these and have happily been able to alternate between 2 & 4WD. The local SuB dealer told me this also, I'll be sure to post my results when I get round to installing the switch. Which at the moment I don't need to if I'm already in FWD.....??? I might check the wiring anyway, see if I can find any abnormalitites or something of suspicion. As for the torque bind issue, cheers for that, will do! muppit Quote Link to comment Share on other sites More sharing options...
Spazz698 Posted June 13, 2005 Share Posted June 13, 2005 Cheers for the replies, Yeah it's a New Zealand car, so 2.0l. I layed a mild pad in the old mans (gravel) driveway couple days ago testing it out, and like me, he's pretty sure it's FWD only. Being a nanna's car I think it'd have trouble 'lighting up' all wheels on solid ice, so to do a skid was pretty exciting for me lol I have a 93 (w/2.2L) auto and I have absolutely no problem losing tread on dry pavement Quote Link to comment Share on other sites More sharing options...
All_talk Posted June 13, 2005 Share Posted June 13, 2005 Is the TCU showing any codes... "power" light always on or flashing? You might try monotoring the voltage/duty cycle going to the "C" solenoid. The procedure for checking TCU codes and the pin outs for the connectors are online somewhere, I'll try and hunt them down if you need them. Look here for a little more info on how the 4EAT system works and the "torque bind" issue (not your problem). http://www.ultimatesubaru.org/forum/showthread.php?t=36459&highlight=duty+4eat+all_talk Gary Quote Link to comment Share on other sites More sharing options...
subyrally Posted June 13, 2005 Share Posted June 13, 2005 ive heard a lot about issues with the 4eat tranny and the center diff taking a dump on em past 120k. im not sure if thats all the 4eat autop trannies, but, i have seen quitea few awd cars with dead center diffs. i really would like to see a mechanical replacememt for the electronic center diff. Quote Link to comment Share on other sites More sharing options...
sregor13 Posted June 18, 2005 Share Posted June 18, 2005 Your right there is a lot of opinions saying that no harm will be caused from driving with the Fuse in. A lot of people have tried to make the above claim. No one has been able to give a scientific explanation. Someone tried once and it sounded very convincing but the next user shot them down. So I drive with it in. Quote Link to comment Share on other sites More sharing options...
subyrally Posted June 18, 2005 Share Posted June 18, 2005 using the fwd fuse to drive on a daily basis can cause damage to the diff if it isnt already gone bad. the center diff is electronic and putting the fuse in puts the solinoid to 100% duty, which can cause it to over heat and burn out permanatly. from what ive heardm there isnt much improvement in gas economy in fwd as opposed to awd. but i could be wrong on that. Quote Link to comment Share on other sites More sharing options...
sregor13 Posted June 18, 2005 Share Posted June 18, 2005 using the fwd fuse to drive on a daily basis can cause damage to the diff if it isnt already gone bad. the center diff is electronic and putting the fuse in puts the solinoid to 100% duty, which can cause it to over heat and burn out permanatly. from what ive heardm there isnt much improvement in gas economy in fwd as opposed to awd. but i could be wrong on that. You are the first to explain it like that. I have still seen this disputed. Are you saying the Solenoid is Open when the Fuse is in because there is a milivolt running to it, Therefore potentionally it will burn out the Solenoid? Quote Link to comment Share on other sites More sharing options...
idosubaru Posted June 18, 2005 Share Posted June 18, 2005 you won't save gas mileage inserting the fuse, nothing meaurable anyway because the internal AWD components of the trans add most of the drag associated with gas mileage degredation. how are your tires? do they all match fairly well? tread depth and pressure correct? improper tire matching can cause the AWD to act weird, though in my experience it causes the trans to lcok and unlock the transfer clutches at wierd times. so it doesn't sound like your problem, but still something simple to check. how much are your tires slipping? alot? typically they will chirp or spin out a little bit before the TCU detects slippage and varies the transfer clutches. if the tires get worse i imagine they could slip quicker and make more noise before the TCU kicks in and moderates the torque distribution to the rear. if they are lighting up the entire time you're on the gas pedal then you're definitely in FWD. if it's temporary but longer than it used to be i may suspect the tires. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted June 18, 2005 Share Posted June 18, 2005 if it is indeed in FWD and a transmission issue then the cause of the problem will determine the severity of this issue. the plausibility of how many miles you can drive the FWD fuse in place is kind of off topic until we know more. it may relate, or may not. i personally think it's possible and an interesting discussion, but not ready for that yet. if you are lighting up the tires then it sounds like you might be driving around in normal mode where the 4EAT trans is putting only 10 percent power to the rear. when i floor my 4EAT trans one front tires slips for a second and then the TCU detects this and distributes more power to the rear and the slipping tires stop. i can imagine a situation where your tires slip but the TCU doesn't do anything....and this would be normal and not harmful to your transmission. it would be normal in that it's a normal driving charateristic for the trans (10 percent to the rear) but abnormal in that it doesn't change the power distribution due to slipping. the 4EAT is always in a 10 percent power distribution to the rear mode...and only changes that when it slips. so if you're always in that mode then you won't necessarily harm the trans. i can also imagine scenarios that are damaging to your transmission, depends in the nature of the problem. i'd say monitoring the TCU and Duty solenoid C is a good idea to see if they are doing what they should be doing. check continuity to that solenoid and start checking the circuit sounds like a good idea. Quote Link to comment Share on other sites More sharing options...
subyrally Posted June 19, 2005 Share Posted June 19, 2005 You are the first to explain it like that. I have still seen this disputed. Are you saying the Solenoid is Open when the Fuse is in because there is a milivolt running to it, Therefore potentionally it will burn out the Solenoid? basically, when you put in the fuse, you are sending an uninterupted power source to th solinoid, normally, it is regulated however its needed for traction. when it is left alone, it turns on and off as needed, thus giving it a chance to cool off and also to maintain the best traction level to the wheels. when you put the fuse in, is constantly engaged, which i think its a powered "off" style circut. when it cant turn off, it builds up more heat than it was designed to deal with for prolonged periods. and thus, has the possibility to burn out. its not definate, but i dont reccomend running in fwd. peace tim Quote Link to comment Share on other sites More sharing options...
Muppit Posted June 19, 2005 Author Share Posted June 19, 2005 Interesting to find out how the TCUworks with torque shifting etc, I always thought it was a 50/50 split, I'm still learning about the inner workings of SuB engines. Does it make any difference as to the ground type? For example from dry tarmac to wet grass? I expereinced some slip yesterday on the wet road, but it didn't last long - say a few seconds, yet it'll sit in one place for as long as I hold my foot down on the old mans lawn? My tires are pretty sweet, especially the fronts as I had them replaced few months ago. Will check the pressures tho to be sure on that one. As for monitoring the TCU & C Solinoid, is this something easily done by a realitively mechanically-minded person such as myself? Does this require electronics testers and whatnot? If the problem is intermittent, which it could be, electronics in my opinion are normally the first things to start doing their sh-t intermittent, so if the above applies, it probably would be a good idea. Regarding the fuse issue, of all the stuff I've read on this, i haven't yet decided on whether or not it's worth trying it - interesting to hear the possibility of burning out the solinoid, as well as the issue being with the trans, not the AWD itself so resulting in FA fuel economy....i'm in town tommorow so will stop in and talk to one of the mechanics on this issue, see what his thoughts are...with fuel prices doing what they're doing, and being the poor student I am, every little bit helps. Appreciate the feedbacks! muppit Quote Link to comment Share on other sites More sharing options...
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