90' Suby Legacy AT slips/hesitates in 3rd gear

[wyomikey]

I'm new,...and know this has probably been covered numerous times. 90' Legacy Sedan automatic 114K miles. Have had the car for about 6 months and have had this problem since i purchased. Previous owner had replaced the tranny,but didn't get specific on the reason why. Shifts great 1st to 2nd, 2nd to 3rd it has a delay anywhere from a couple seconds to about 7-10 seconds. 3rd to 4th is great. The lag is a lil worse when accellerating uphill. when the tranny drops from 4th to 3rd to pass the RPMS will kick up and it lags for a couple seconds before kicking in. Other than that she runs strong !! I had read/heard that it could be the throttle position sensor,so i replaced with no change. It does the same when in manual mode or when shifting from 3 to D. Hope y'all can help!!

[wyomikey]

bump

[Legacy777]

Welcome to the BBS.

Usually shifting issues like that are related to an improperlly adjusted brake band, however the brake band handles the 1-2, & 3-4 shift. The 2-3 shift is more clutch related I believe. There may be something up with internal line pressure that may be causing the problem. My suggestion would be to take it to a reputable transmission shop.

However, hopefully someone can shed a little more light on the subject.

Here's a scan from the factory manual that talks about the brake band.

http://main.experiencetherave.com/subar ... andadj.jpg

[wtdash]

Hi,
Another thing to try is a different TCU/tranny computer. Not likely the cause, but since the trans was already replaced it could be involved.

Also, if you get a newer TCU from a '92+ you can do THIS mod, that may help.

I'd also suggest doing an ATF service. But check yours for that burnt smell first.

GL,
Td

[wyomikey]

Welcome to the BBS.

Usually shifting issues like that are related to an improperlly adjusted brake band, however the brake band handles the 1-2, & 3-4 shift. The 2-3 shift is more clutch related I believe. There may be something up with internal line pressure that may be causing the problem. My suggestion would be to take it to a reputable transmission shop.

However, hopefully someone can shed a little more light on the subject.

Here's a scan from the factory manual that talks about the brake band.

http://main.experiencetherave.com/subar ... andadj.jpg

THanks for the info i will check that out!!

[wyomikey]

Hi,
Another thing to try is a different TCU/tranny computer. Not likely the cause, but since the trans was already replaced it could be involved.

Also, if you get a newer TCU from a '92+ you can do THIS mod, that may help.

I'd also suggest doing an ATF service. But check yours for that burnt smell first.

GL,
Td

I have checked the fluid it's pretty clean and without the burnt smell,but does seem a little overfilled. You do make a good case about the TCU. I'm not sure what year car the replacement tranny came from. Looks like i'll have to look for Serial numbers....

Oh one other thing,...i know that the tranny is a suppose to be 4 spd auto,but is it normal for them to drop about 200 RPM at cruising speed,almost as if it has a bit of an overdrive? THanks Again!!

[wtdash]

Oh one other thing,...i know that the tranny is a suppose to be 4 spd auto,but is it normal for them to drop about 200 RPM at cruising speed,almost as if it has a bit of an overdrive? THanks Again!!

Yeah...it's when the TC locks up, I believe...almost feels like 4.5 gear, in my experience.

Get the number off the bellhousing - starts w/a TZ.... - if it's still there. That can be decoded.

Td

[wyomikey]

Oh one other thing,...i know that the tranny is a suppose to be 4 spd auto,but is it normal for them to drop about 200 RPM at cruising speed,almost as if it has a bit of an overdrive? THanks Again!!

Yeah...it's when the TC locks up, I believe...almost feels like 4.5 gear, in my experience.

Get the number off the bellhousing - starts w/a TZ.... - if it's still there. That can be decoded.

Td

Yeah,...that's exactly what it's like!! I just found a site that talks in detail about the 4EAT. Man that's one complicated transmission system. As much as i like doing my own repairs, I think i will just take her to a shop and have them diagnose the problem.

[wyomikey]

Welcome to the BBS.

Usually shifting issues like that are related to an improperlly adjusted brake band, however the brake band handles the 1-2, & 3-4 shift. The 2-3 shift is more clutch related I believe. There may be something up with internal line pressure that may be causing the problem. My suggestion would be to take it to a reputable transmission shop.

However, hopefully someone can shed a little more light on the subject.

Here's a scan from the factory manual that talks about the brake band.

http://main.experiencetherave.com/subar ... andadj.jpg

Hey Josh,...went to your website,....very helpful!!! I went to your Notes/Tips under "transmission related" and found the self diagnosis and TCU codes breakdown,....very good info to have. I found i have a code 24 "duty C solenoid", and code 33 "speed sensor #2".

[Legacy777]

Does the power light flash 16 times on startup? If not, those codes might be stored codes. I'd suggest clearing the codes by pulling fuse 14, EGI/TCU fuse for about an hour. You may want to check your ECU for any stored codes, because it will clear as well.

After clearing the codes, drive the car and see if it acts any differently, and then check the codes again.

When you check the trans fluid, the trans needs to be up to normal operating temp (if using the HOT dipstick markings), which is about 10-20 miles of driving. Park on a flat surface, slowly cycle the gear selector from P to 1 and back to P. Leave the engine running and then check the fluid level.

[wyomikey]

Does the power light flash 16 times on startup? If not, those codes might be stored codes. I'd suggest clearing the codes by pulling fuse 14, EGI/TCU fuse for about an hour. You may want to check your ECU for any stored codes, because it will clear as well.

After clearing the codes, drive the car and see if it acts any differently, and then check the codes again.

When you check the trans fluid, the trans needs to be up to normal operating temp (if using the HOT dipstick markings), which is about 10-20 miles of driving. Park on a flat surface, slowly cycle the gear selector from P to 1 and back to P. Leave the engine running and then check the fluid level.

Yeah about 16 flashes is right,..it hasn't flashed in a while. I will pull the fuse and see what happens. As for the trans fluid check i was always checking the level while in neutral,....and yes i was checking the HOT side of the dipstick. I may not have let her warm up long enough,my drive to work is about 10 miles each way. Thanks again for your help,...and your website!! Mike

[Legacy777]

The trans should be in Park. Then slowly cycle from park to 1, and then back to park.

[wyomikey]

Well i did as you (Legacy777) suggested. Pulling the fuse did clear the codes. It now just flashes steady in both modes. I drove her to work, checked it,drove her home and checked again,...no codes!! Wooohooo!!! LOL!!! Now as for that hesitation problem in 3rd gear,...i mentioned the delay or lag from 2nd to 3rd which also happens when it kicks down from 4th to 3rd on accelleration. I forgot to mention that it sometimes will have a "braking" sensation from 2nd to 3rd as well. Funny part about that is when it does this "braking" it feels like it's engaging gear better.......make sence???

[wyomikey]

buuuuump!!

[Legacy777]

You can try adjusting the brake band to see if that helps. It can be rather difficult to get to, adjust, and set properly.

I'd really suggest taking it to a trans shop to take a look at it. Automatic transmissions either work or they don't work and diagnosing something like this really requires opening up the trans. A shop may have a better idea what's wrong and what it would take to fix it.