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View Full Version : 4l60e works sometimes.....



Darrenmb
04-16-2020, 01:34 PM
Ok, in case there are different readers in this section versus the engine or pcm section, heres a little background.. complete engine and drivetrain from a 94 pontiac formula, into an 83 jag xj6, motor has lt4 hotcam, springs and 1.6 rockers, and is tuned by Moe, not that any of the last bit matter, but laid it all out there just in case... motor looks like it was made to fit in the jags engine bay and car is a total beast, (when it decides to play nice)
Here is the issue... if i drive the car sedately its a dream, shifts fine everywhere, and pulls nicely, but, if i get into it, i have issues galore.
If i pull away from a stop aggressively, it will shudder then make a pop sound and all forward gears are gone and trans is making a rattling sound., if i put back in park, then back to drive, 9 times out of 10, its fine again, once in a while its not fine and has to sit a few before she will move.
If car is already moving and i push her hard, she will downshift hard, and make the pop, and again all forward gears are gone and shes rattling. ...
Before I tear it out and take to a shop, is there anything that jumps to mind that voild cause this? I used to be a mechanic 30 years ago, but was mostly engine and ac work, trans stuff we always farmed out!

Oh and torque converter is stock... and i never lose reverse!
If trans has to come out nows the time to do it while everything is slow, as i am stuck dealing with an issue in the UK and cannot get there, and due to time difference i can only call over there until noon out time!!!

harner
04-16-2020, 01:49 PM
Dumb question, how does the fluid look and is there fluid in it? Does the trans have pressure? Driveshaft length ok? Maybe check the pan and make sure the filter is ok.

Just some things to check before taking it completely apart. These trannies are made of glass but it's worth a convo with CPT if you want it built right.

Darrenmb
04-16-2020, 02:07 PM
I should also mention that when its not working selecting gears manually doesnt help, even 1st, i can watch myself selecting gears on the scan9495, so i know i am hitting 1 not just 2.

Darrenmb
04-16-2020, 02:15 PM
Fluid is bright red and full, however thats because i had to fill it, when the guys pulled it out of the formula they came out the top, so all trans fluid dumped out the tail.. driveshaft is correct length, as it was measured from rear end flange to yoke u joint, with yoke slid out 1 inch., havent dropped pan, and i do have a code 83 which is the pwm, however being as its a 94, its a false code, been told it means the bin file is from 95. I suppose trans could be a 95 and bin is 95 for a reason, but would that cause my issue? I guess i need to go get under it and dig around.... thought inwas done getting dirty when i put the hood back on the car...

SSlowBoat
04-16-2020, 02:33 PM
Fluid is bright red and full, however thats because i had to fill it, when the guys pulled it out of the formula they came out the top, so all trans fluid dumped out the tail.. driveshaft is correct length, as it was measured from rear end flange to yoke u joint, with yoke slid out 1 inch., havent dropped pan, and i do have a code 83 which is the pwm, however being as its a 94, its a false code, been told it means the bin file is from 95. I suppose trans could be a 95 and bin is 95 for a reason, but would that cause my issue? I guess i need to go get under it and dig around.... thought inwas done getting dirty when i put the hood back on the car...

If you run a pwm trans on a non pwm 94 bin, you will have issues. conversely, if you run a non pwm trans on a pwm bin, you will have issues. look at the sticky written by @Cahall about 4l60e interchanges and differences in the transmission section.

sounds like something mechanically is screwing up in the trans when the line pressure increases. maybe the servo is moving too far or a check ball is stuck or missing a spring. also the pump could be on its way out, converter could not be shimmed properly ( no more than an 1/8" clearance between converter and flexplate with converter pushed all the way into trans pump. shim with washers or shims between converter and flex plate) (blew a pump once with about 100 miles on trans, it even survived some dyno pulls running an obd2 trans on an obd1 94 bin ((big NO-NO))

that leads me to my third idea, are you SURE the trans came out of a 95 and is infact an obd1 trans? if its an obd2 trans it will 3 neutral 2 downshift and beat up everything internally. will run fine when babied, but when you put your foot in it it will do all kinds of weirdness.

Darrenmb
04-16-2020, 03:36 PM
I willl find out more this weekend, i dont know year of transmission, only what i was told, that entire driveline was from 94., i never questioned any of it until until i saw the 83 pop up, dropping pan will be first, that i can see.it there s a pwm can also check the connector i guess, and the wires from pcm, i have the pinouts, so hopefully i can at least nail that down.

Darrenmb
04-16-2020, 03:57 PM
Pin 6 on the blue plugin at pcm is empty, so 95 bin is pointless regardless, now i guess i have to pull pan juat to verify correct trans, and go from.there

Injuneer
04-16-2020, 06:44 PM
DTC 83 was used for both the M6 (reverse lockout) and A4 (PWM solenoid) in 1995 only. In 1994, DTC 83 is only used for the M6. Seems odd that a 1994 PCM program would run the A4 diagnostic and report DTC 83. May indicate a 1995 program trying to control a 1994 4L60E..... just a guess.

Darrenmb
06-08-2020, 01:33 PM
I know it's been a while, was waiting on another transmission that never showed, sooooo. I pulled existing one out on Saturday, it is indeed a 94, 4ffd being the code stamped on it, and am taking it tomorrow to a local trans shop, will keep you guys updated on what the issue turned out to be..
As a side note, i sent the pcm back to Moe and he returned my bin back to a 94, so all should be good there, also when removing it, i noticed that once torque converter was unbolted from flex plate i had a heavy 5/16, gap, not 1/8 like its supposed to be, and once unbolted, not only did it slide a long way back, but i was able to wobble the whole thing in every direction.... also had quite a bit of wobble at output shaft as well..

Darrenmb
06-13-2020, 10:30 AM
For anyone following this, i got trans back today, the issue was front sprag had come apart! Now to get motivated and get under car to reinstall it!!!

Darrenmb
07-15-2020, 07:43 AM
Think i may need a new transmission shop... they are telling me things that are obviously lies, first was they changed the governor, and 2nd was that its a throttle cable issue, i do t have a 700r4, its a 4l60e... i already called them out on it and the guy on the phone said he would talk to his builder to see whats going on.. they have had car now for 2.5 weeks. My guess it they are trying not to pull trans back out!. My queation here is. If i can watch it command 1,2,3 and 4 and it goes to neutral in 4th could it be a harness issue? My understanding is is that if i get 1,2 and 3 it means all the solenoids are working correctly. Just want my ducks in a row before i raise hell when they call me back. Also just so all info is out there, i also still get lockup in 3rd.

Thanks
Darren

P.s. if i need to re-ask in transmission section let me know.


Copied and pasted from pcm issues...
Thanks in advance for any help.

Darrenmb
07-15-2020, 07:48 AM
Guess i should have started a new thread.. if any infonis missing, please ask me..
94 4l60e ( whole drivetrain actually) swapped into 83 jag
Trans was rebuilt, (bench build) and i reinstalled, as stated above i have 1,2 and 3 but 4th is neutral, can watch all commands, tcc is working. Shop called back and said he kisspoke, instead of governor he meant servo, has been replace issue persists. Also, it feels as if 2nd has no engine braking sometimes.. if thats relevant.