PLEASE Help Its the Transmission Again

[daluvabull]

Oct-18 Update

Had alternator rechecked at Oreilly's- passed

Did not know exactly how to check for AC through battery- my voltmeter leads got very hot when contact made with positive/negative posts.

Cleaned used dielectric grease on alternator contacts and gound under passenger side intake.

Replaced alternator 2-prong plastic female socket.
It was brittle and crumbled when removed
Sodered used socket to leads, wrapped with electric tape

Noticed that the plastic at the base of the alternator positive bolt is cracking away.

Went for a test drive
Shifted fine until hard acceleration
Stalled, had to crank and push accelerator multiple times to restart
Power light still does not illuminate at start up

Probable next steps:
Replace alternator with a new one
Test was not performed under hard acceleration
Leaning towards Trevor's suggestion- THANX
Is a 110 amp preferrable to, or worth the extra money as, a 95?

Again, your suggestions, time and knowledge is a appreciated.

Peace,

Jeff

[daluvabull]

Oct-24 Update:

Installed new alternator
Results
1. No more warning lights at hard acceleration
2. Still no power light at start up
3. Continued irratic shift behavior
a. Intermittant correct shifts
b. Intermittant start in 3rd from stop
c. Shift down to 3rd while on cruise control at 65 mph
4. Irratic engine stall on hard acceleration
5. Tach not working properly.

Any ideas...

TCU?

THANKS

Jeff

[daluvabull]

Bump ******

[svxistentialist]

Originally Posted by daluvabull

Bump ******

Is this a '92 car Jeff? All SVXes are getting on.

I note you are on your third gearbox. You should get or borrow a multimeter that will measure for stray AC currents like Trevor suggested, even though you have replaced the alternator.

When tracking faults with the WSM one of the possible cures that comes up again and again is the TCU. Now it is generally last on the list, so don't go jumping in that direction just yet.

However, what can go wrong most easily is the wiring looms [you americans probably say "cord" ] feeding signals to and from the TCU. It is bloody difficult to get these connectors to extract from the TCU, and yours must have been taken out and refitted loads of times. You should have a look under your dash and make sure that no damage has happened to these block connectors or the wires feeding into them. Something damaged or loose there [maybe from using a pliers to extract] could be giving you this strange behaviour.

Worth a look

Joe

[NiftySVX]

Hey I know I'm late to the party here, but I've read over your thread here and I have the following suggestions for you. Everyone, including myself, likes to run in and go down for the kill before you think about the basics.

FIRST:
TAKE OFF YOUR FILTER IN THE COOLER CIRCUT AND PUT IT IN THE TRASH. it is not necessary and all it could possibly do is cause a problem. If you've had this filter all along through all these different transmissions, you could have the answer to why you keep burning them up right there. I'll assume you're replacing the element at each trans change, but still, GET RID OF IT. Cold shift issues can be caused by a restricted cooler circuit as the fluid is thicker when cold and it will be even more restricted at low temps.

Second, check the fluid level and condition. Ensure that with the engine running the fluid is very close to or just below the "low cold" level when the trans temp is below 75F and that it is somewhere between "full cold" and "full hot" at 176F. I like to keep mine a bit below the bottom tick of the "hot" range at 150 pan temp. Don't overfill! Error on the low side! An overfull 4EAT is a dead 4EAT!!

Okay now check your voltage to the TCU and make sure you're getting constant power to it and it's not loosing power while the car is going down the road. That would cause all kinds of odd problems, I think.

Third, check your solenoids. Duty B is lockup control, duty A line pressure, and solenoids 1 and 2 are shift solenoids. Check the resistance of each of these at connector T2 and again at the TCU harness by backprobing with a T-pin, which is a T shaped pin for quilting available at wal mart. If you find you've got a shift solenoid laying down on ya, this would explain alot of erratic shifting conditions. If the solenoids test okay, then you can go back and start thinkin more about a control side failure outside of the trans case.

Then, after that, I would really reccomend you check the base line at the pump pressure test port. heat the fluid up to operating temp (somewhere around 176f) and check your line pressure. If you don't know that you've got good base line then you're blind and deaf in a trans diagnosis.


Now, you should have a good idea of your transmission unit itself and its condition.

[Trevor]

Originally Posted by NiftySVX

Hey I know I'm late to the party here, but I've read over your thread here and I have the following suggestions for you. Everyone, including myself, likes to run in and go down for the kill before you think about the basics.

FIRST:
TAKE OFF YOUR FILTER IN THE COOLER CIRCUT AND PUT IT IN THE TRASH. it is not necessary and all it could possibly do is cause a problem. If you've had this filter all along through all these different transmissions, you could have the answer to why you keep burning them up right there. I'll assume you're replacing the element at each trans change, but still, GET RID OF IT. Cold shift issues can be caused by a restricted cooler circuit as the fluid is thicker when cold and it will be even more restricted at low temps.

Second, check the fluid level and condition. Ensure that with the engine running the fluid is very close to or just below the "low cold" level when the trans temp is below 75F and that it is somewhere between "full cold" and "full hot" at 176F. I like to keep mine a bit below the bottom tick of the "hot" range at 150 pan temp. Don't overfill! Error on the low side! An overfull 4EAT is a dead 4EAT!!

Okay now check your voltage to the TCU and make sure you're getting constant power to it and it's not loosing power while the car is going down the road. That would cause all kinds of odd problems, I think.

Third, check your solenoids. Duty B is lockup control, duty A line pressure, and solenoids 1 and 2 are shift solenoids. Check the resistance of each of these at connector T2 and again at the TCU harness by backprobing with a T-pin, which is a T shaped pin for quilting available at wal mart. If you find you've got a shift solenoid laying down on ya, this would explain alot of erratic shifting conditions. If the solenoids test okay, then you can go back and start thinkin more about a control side failure outside of the trans case.

Then, after that, I would really reccomend you check the base line at the pump pressure test port. heat the fluid up to operating temp (somewhere around 176f) and check your line pressure. If you don't know that you've got good base line then you're blind and deaf in a trans diagnosis.


Now, you should have a good idea of your transmission unit itself and its condition.

Hooooray, at loooong last absolute logic.

"check your line pressure. check your line pressure. check your line pressure."

This essential basic and obvious requirement, has here been continually passed over for years.

[major7venth]

Not sure what is/ or is no longer connected with your 4.44 so, Run a trans. diagnostic?, any codes?. Check battery with a carbon pile battery tester,(take battery to a battery shop/parts house,they can test it for you. (and be sure battery connections are good) if faulty battery, replace battery. Check impedence on the trans. resister (if its is still being used with your 4.44) (located behind the battery) ((15 ohms, (I think, check the book to be sure. any impedance is usually good) Check Alternator output. These things will be sure the electricals are keeping the TCU happy. Change Trans. filters and replace trans. fluid with Synthetic, if no improvment, Your 4th trans is probably next. Good luck,tell me how it goes, would be interested to know the final remedy.
M7

[b3lha]

Originally Posted by daluvabull

3. Continued irratic shift behavior
a. Intermittant correct shifts
b. Intermittant start in 3rd from stop
c. Shift down to 3rd while on cruise control at 65 mph
4. Irratic engine stall on hard acceleration

Please test your TPS and your ATF temperature sensor.

[daluvabull]

THANKS to all who had positive input, my transmission troubles are gone- for now. There was a short at the TCU plug where a shift kit was added. The shift kit was removed and a new plug spliced onto the harness and a the TCU replaced by a used one. The 4.44 now shifts correctly. I now am in the process of identifying vacuum leak that is causing engine stall at high temps. At 17 years old and 187k miles the hoses are brittle.

Again THANKS,

Jeff