Rear wheels slow to engage, need help!
 

Last spring, I ended a thread on this subject hoping that the tranny rebuild I was getting would cure the problem, but it didn't!!!

The story in short.....

When I floor it, the front wheels spin quite a bit before the rear wheels engage (with a big jerk).

The plan.....

So I have a new tranny in, (NIL FIX) and yesterday I changed the VSS that is mounted on the transfer case housing..... Guess what? STILL NIL FIX! The front wheels still spin when I floor it!

The tranny tech told me that "everything looks normal" in the tranfer case section" when he rebuilt it....

I need suggestions! Anybody had this problem before? How was it fixed?.... Next thing to change would be the duty solenoid or the TCU..?? (about the TCU, the diagnostic mode says "No Problem"!!!!)

Help me!!!!!

Thanks

Re: Rear wheels slow to engage, need help!
 

I gotta ask...

What did it cost you to rebuild the tranny in Montreal in our ain't-worth-a-damn Canadian dollars?

I have to start saving up... Seems it's not a matter of if, but when...

VK

The complete rebuild cost me about $2100 CDN ($1300 for our American friends).... Not bad at all considering what some other people paid!

That's a good price, to be sure. My SECOND rebuild (on the REAL SVX tranny cost me 1200.00). It sounds to me like your transfer clutches are gone, but, not actually "feeling" what it's doing makes it hard to tell. When my transfer clutches were going, It would especially show itself on a hard left turn from a stop (like when goosing it to beat traffic out of a stop sign). The car would bog down and shudder before it straightened up. Of course, this was a Legacy tranny into an SVX rear end (mismatched gear ratios). Are you sure you don't have a Legacy trans in your car?

I bought the car 3 years ago (lease return) and it was working perfectly (couldn't spin the wheels even on gravel!). Then, is slowly started.... At first, the delay was very small but it kept growing. Meanwhile, the tranny started slipping so I had it rebuilt.

I explained the problem to the tech and he looked at the transfer case section closely and found no defects.... He say that the problem comes from somewhere else. So yesterday, I changed the VSS with no improvement. Now, Should I change the duty solenoid??? The TCU??? or...???:confused:

Is there a way to reset the TCU? 'cause the it gives me no trouble codes.... maybe resetting...:rolleyes:

had the same problem
 

Joe, Before my transmission gave out I had the same problem and symptoms you have. My very reliable and competent dealer was 90% sure it was a wiring harness issue, something that would likely not be replaced during a rebuild, which may be why you still have the problem. Getting the new/Subaru remanufactured transmission immediately solved the problem. Luckily I never did replace the wiring harness ($500) because my transmission blew out 3 months later and it would have been a waste to replace the harness on a soon-to-be-dead transmission.

Jeff

Re: had the same problem
 

Sorry, I forgot to mention that the VSS I replaced, came with the wiring harness... (94 model) so this has been taken care of.

Joe, there's a procedure for reading stored codes (from previous problems). I have the procedure at home, or, if SVXcess comes along, perhaps he can post them -- or someone else, if they have them. Sorry. I feel so helpless. The thing about it is, the TCU will only tell you if a problem is electronic. If the problem is mechanical (which is my guess), it will not give you a code. The only time an electrical problem code will not show up, is when the unit in question is just within tolerance -- causing the part to malfunction due to inefficiency, but, still telling the TCU that it's "within tolerable limits."

Hello Joe,

I too share your problem. No rear wheel drive:( What a bummer.

Got not trouble lights? I have none either.

Check the transfer pressure? Be there in person when your tranny person does it. It is the plug on the side near the top of the transfer housing on the driver side. It is 10mm(1.0) {Corrected 10-26-001} with an o-ring seal. A 1/8"NPT pipe nipple will grab a few threads. There should be pressure there when the car is running and the trans is in R or D.

My car has no pressure there. I have concluded the transfer valve is stuck. This is really a pilot valve that works the transfer valve and the solenoid is in between. Any one of these items could be stuck: pilot, transfer or solenoid. There are no warning lights if these stick. The only way to check is measure the pressure at that port. The maual has spec's for the proper values.

The question is...... Why does it stick? It could be worn out because it is always in motion or is it just gummed up? I would like to know if you find out.

Is your TPS original? Have you had a TPS code from the ECU? How many miles on the car?

This info would be helpful.

I can live with $2100. (Not that I'm hoarding a money tree...)

Where'd you get the rebuild done?

VK

Originally posted by svx_commuter
Hello Joe,
I too share your problem. No rear wheel drive:( What a bummer.


i've got that same problem also.
i don't have a 'real job' at the moment, so i've chosen to ignore it.
heh. my ears will perk up if you figure out a solution.
<fingers crossed>
toby

First, thanks everyone for your replies.... I'm "kinda glad" that I'm not the only one with this problem... :rolleyes: Together, we might find a solution (hopefuly)


Arebubjay I checked the codes (recent and previous) this morning and the TCU
shows "NO FAULT" (rapid blinking)... :(

svx_commuter: The transfer pressure eh... Yes, I can do this but.... Do you say
that I need to drive the car with a gauge connected or just up on a lift?

The TPS on the car is original and the car has 207000 Km, but can you explain the relationship between the TSP and the ECU/transfer clutches? :confused:

VK (and others interested); I had the transmission done in a town called
"Chambly". It's about 30Km south of Montreal (see below)


Chambly Auto Transmissions
1275 Bourgogne, Chambly, QC J3L 1X8
Phone: (450)447-7606

So, the next step.... My suspicions now are focused on the duty solenoid, But if I do open the back end of the tranny, I would probably change the transfer clutches by the same occasion.

Winter is approaching rapidly, I need "the beauty of wheel drive" back ASAP!

P.S. Toby, I will let everybody know if I find a solution.....

Yes you can check the transfer clutch pressure with all four wheels on the ground, or on the lift or while you drive.

You had the transmission rebuilt, can I assume this did not include the transfer section or should the rebuilder being doing this work for you? Personally I think it was missed by the rebuilder. No transfer pressure? The rebuilder does the work at their cost. However I do not know the arrangement of the rebuild. Can you tell him he missed something? Have him replace the transfer valve and solenoid assembly?

The TPS is used for a lot of things. Shift points is one of these. I just replaced my TPS and the car is very different. More responsive under light throttle and the 2nd to 3rd slip has gone away for 5 days now. The TPS tells the ECU and TCU if you are opening or closing the throttle. When the TPS is not working correctly these devices (TCU ECU) may think your foot is traveling in the opposite direction from what it is really doing.

TPS is also used to adjust the transmission line pressure and the transfer clutch pressure.

I would like to know if the transfer valve wears out or clogs up? Are the parts worn and do not work any more or has the fluid turned to sluge and clogged up the works? Both of these result in no trouble code.

You said "eh." :D

Transmission pressure tests:
Line pressure for idle in P,N,D,3,2,1 = 64 to 82 psi in R = 85 to 100 psi
At stall speed about 2400 rpm, short term or you burn up the clutches unless the wheels can spin. D,3,2,1 = 164 to 182 psi and in R = 206 to 230 psi

For the rear section, transfer pressure in D or R = 7 to 11 psi at idle and for stall speed 104 to 114 psi.

This is from section 3-2 page 121 of the manual.