Jump to content
Ultimate Subaru Message Board

Opinions/Information wanted - 4eat AWD - AWD not functional


Recommended Posts

OK guys, I've got a 1990 Legacy L AWD with 197K miles. Abso-frigging-lutely love this car. It's my first Subaru and it's the best daggone car I've ever owned.

 

Anywho, AWD recently went buh-bye. Dunno if it's a failed Duty C solenoid, bad wiring, naughty TCU, or burnt-out clutchpack but only the front wheels are moving on hard throttle launches.

 

I NEED my AWD to work here in WV. I drive 93 miles each way 5 days a week for college and I see every type of weather you can imagine. My problem is...my mechanic. My father does all my mech. work for me as I'm not really well-versed in the art of turning a wrench. I know enough to do electrical things and can do most basic maintenance but the items that need to be torn down are his area.

 

Dad doesn't know jack about Subarus and...well...I don't have any actual knowledge myself. I have been obsessively reading, however, since my troubles started and I think I have a good idea of how the 4eat works.

 

He thinks it's a wiring problem. I'm nearly certain it's a burnt-out clutch pack. It could also be a bad Duty C solenoid though I dunno how as it's not locking the rear (meaning 100% voltage to the solenoid).

 

How hard is it to correctly rip out the tail-housing and replace the clutch pack bits (friction plates and such) if that turns out to be the problem? I can get the plates for around $3.50/ea. so that's a nice, cheap fix...just very labor-intensive.

 

If it turns out to be a faulty Duty C solenoid, which'll be a while before I can get a multimeter in there to test it, where can I find one and approximately how much is it? This seems like a relatively simple fix but if it's too costly, I'll take my chances on the $100-been-sitting-for-a-year-owner-doesn't-know-what-condition-it's-in tranny I found locally.

 

Simply put, what would y'all do?

 

My sincere apologies for the length of this post...

Link to comment
Share on other sites

You should be getting abour 10 ohms off the duty C solenoid.

here's the connection:

10420conv1.jpg

 

Here's the connector:

10420conv3.jpg

that is..

4 3 2 1

8 7 6 5

12 11 10 9

13 - - -

 

the dashs repersent NO PINS (there isnt' a pin there), you can only sort of see that in the image.

 

and here's what you get when you grab pins 4 and 11

10420conv4.jpg

 

 

If you get something completely different from that resistance... you may have a fried duty C solenoid.

When i burnt out my clutch pack, when i romped on it i could spin the front tires... and the rear would do nothing.

How does your ATF look? burnt, black, nasty?

 

I've heard you can replace the duty C and the clutch packs with the tranny still in the vehicle... just a little tight i believe.

 

If you want more info on how it works: http://www.ultimatesubaru.org/forum/showthread.php?t=50264

that's how to lock it up, but i wrote a bit about how it works & stuff.

Link to comment
Share on other sites

I'm having the same syptoms. Front tires spin like mad on hard launches (or too much throttle in a tight turn with gravel) but the rears just sit there and follow the car around. No rear-driven motivation whatsoever. That's why I'm leaning more towards a bad clutch pack.

 

Thanks for the quick and very informative reply. I've read your awesome write-up in the USRM.

 

Any ideas on part numbers? Also looking for an estimated cost on the duty c solenoid if anyone knows...

 

Thanks again

Link to comment
Share on other sites

What i want to know, is if the two speed sensors can cause the AWD system to fail, because my 93 leg has the same problem. i wonder if there is a way to test the system by stopping the 12-14v being passed to the solenoid, therefore engadging the AWD system, and if it still fails, then i found the issue. Because i brought my car to a tranny shop and they "CLAIM" the transmission was fully rebuilt, but it doesn't sound true.

 

I'm going to go to subaru and they will tell me what exactly is creating this issue. If there is a sensor that is causing a issue, ill report it to you guys, but it sounds more like i got screwed, and the clutches were NOT replaced, oh well.

Link to comment
Share on other sites

Actually, if i unplug the the tranmission connectors, won't that determine if its a sensor issue, because it SHOULD make it 50/50 correct?

 

But will i damage anything drviing like this, to test it and see if it engadges AWD?

Link to comment
Share on other sites

Hi Folks.

 

OK herer is the deal. If you are getting no CEL light or Tranny temp light, odds are electrically the unit is fine. If you have no Torquebind, then again electrically you are fine.

 

Now the bad news. Your clutch pack is slipping. If you put the car in low or reverse you MIGHT get some rwd, but the clutch pack is glazed, so the clutches arent grabbing. These things happen, as nothing lasts forever.

You may want to try a fluid change, but i sort of think its pointless, unless the fluid is really dirty.

 

 

nipper

Link to comment
Share on other sites

Hi Folks.

 

OK herer is the deal. If you are getting no CEL light or Tranny temp light, odds are electrically the unit is fine. If you have no Torquebind, then again electrically you are fine.

 

Now the bad news. Your clutch pack is slipping. If you put the car in low or reverse you MIGHT get some rwd, but the clutch pack is glazed, so the clutches arent grabbing. These things happen, as nothing lasts forever.

You may want to try a fluid change, but i sort of think its pointless, unless the fluid is really dirty.

 

 

nipper

 

but can something electronic fail and no give a CEL?

Link to comment
Share on other sites

but can something electronic fail and no give a CEL?

 

no (well there is wlays an exception).

 

You will get a light for a stuck valve (open closed or inbetween), shorted valve, non responsive valve or an open circuit.

 

the only thing to check is to make sure the light works.

 

If you just have the begnings of torque bind and no light, a fluid flush is in order, that usually fixes it, or at least buys you time.

 

nipper

Link to comment
Share on other sites

Well what if i get a TAD bit of binding on dry asphalt, but the rear wheels don't engadge? And my fluid is full, and red, not smelling burnt, and the the power light comes on for a moment then turns off checking normal and did a diagnois for the TCU and no codes, shows up normal, but when i checked previous codes, it said VSS #2. What do you think? And i never replaced VSS #2.

Link to comment
Share on other sites

Well what if i get a TAD bit of binding on dry asphalt, but the rear wheels don't engadge? And my fluid is full, and red, not smelling burnt, and the the power light comes on for a moment then turns off checking normal and did a diagnois for the TCU and no codes, shows up normal, but when i checked previous codes, it said VSS #2. What do you think? And i never replaced VSS #2.

 

There always has to be a difficult child.

 

A little torque bind is like a little pregnant. Eventually it gets more apparent.

 

I am assuming the tires all match and are inflated.

 

When you loose a vss you loose AWD.

 

How old is the fluid. The fatc that your slightly binding and the no power im guessing you have a chewed up clutch disc and the rest are glazed, or something akin to that. If i remeber right there are 5 discs in the clutch. Could als be physical damage to the clutches.

 

nipper

Link to comment
Share on other sites

Thanks for the replies all. Anyone know if http://www.bulkpart.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=2&Product_Code=23118A

is the right friction plates to use to rebuild the clutch pack?

 

You do know you need more then just clutch discs. there are seals, and as long as you are there a new solenoid, and a housing (depdning upon damage) and clutch plates to name a few. This is NOT something you want to cheap out on parts on.

 

Someplace on here is a list of parts required to fix it from someone.

Also when i got mine rebuilt the dealer had to match parts up, and couldnt just order them out of the book. I dont know how true that is, but mine also was the desgn change year of 1997.

 

 

nipper

Link to comment
Share on other sites

Heh, actually I had no idea what was required on top of just the friction plates. Thanks for the info. That el-cheapo tranny I found locally is sounding pretty good. Even if most of the internals are bad, if the tail housing is in pretty good shape it's worth $100 bucks. I simply don't have to moolah to get this car fixed by a dealership.

Link to comment
Share on other sites

the local transmission place near my house in NH said they could fix it for 2-400 bucks, depending on how bad it was.

 

ild be suspisous of that andyjo, when the parts form the dealer alone was 498.00.

 

And we all know how much we trust tranny shops.

 

 

nipper

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share

×
×
  • Create New...