crazy tranny issues..

[1.8laser90]

hey guys,
well i have a 90 eclipse 2.0. I replaced the tranny that went bad before i baught the car with one that was suppost to be a jdm, with 40k on it. it was tore down and cleaned before shipped to me. installed it, ran into some issues but got them under control (had 2 plugs backwards). this was over a yr or 2 ago. As long as i can remember, there would be times when shifting from 2nd to 3rd it will rev maybe 100rpm somtimes 200-4rpm(rarely) when shifting. And other times shift nice and smooth like it should. 2 years later and about 14k miles put on it, the tranny is still alive and has the same issues.

Now im driveing it on a daily basis and its gettin anoying. Heres things ive noticed after driving it for awhile.
If you let the car idle in neutral when first starting for the day it usually doesnt do it in the begining of the day or for that first drive to wherever.

when the tranny acts up it will rev up between 2nd and 3rd. Then u may come to a stop shortly after that and have it go threw the gears again and sometimes it wont do itWTF

if it does rev up between 2nd to 3rd when just normal crusing (which is when it usual does it) and you floor it and have it go back down to 2nd and have the engine in the higher rpms (4k and above) and then, shift it wont do i and it never has. it seems to only happen when in the lower rpms or normal driving, never under full throttle. which is when it should do it ?

the tranny doesnt seem weak because the others shifts besides 2nd to 3rd are perfect. Which leads me to believe its not going need rebiult because it does get beet on sometimes and its still normal, no worse, no better, specially over this time.

heres one other thing that gets me, i have come to figure out that if u disconect the battery for a min or 2, the tranny will shift PERFECT for the next couple days. then gradually go back to its good and bad days..WTF makes no sense to me. I have tried swapping out tcu's and still same issues. I really have no clue what it could be. i could really use some help on what to do, test exc.. i can post up videos if needed also

 

[HighPSI TSi Guy]

Is the fluid full? sounds like front clutch is slipping. Could be due to worn clutch, line pressure issues, or fluid temp. Put good fluid in it and make sure that it's full and see what it does.

 

[1.8laser90]

fliud is full. new fliud was put in about 10k miles ago when the pan gasket was changed and new filter installed. Its still clean and smells normal 10k miles later. If the clutch in the tranny was whore out, wouldnt it slip all the time not just 1 day and not the next or shift perfect and then the next shift not? Also why if you disconnect the battery for abit does it shift perfect for the next acouple days? thats what makes me believe its not worn clutchs.

I checked the engine and tranny codes today, came up that everything was fine

 

[HighPSI TSi Guy]

fliud is full. new fliud was put in about 10k miles ago when the pan gasket was changed and new filter installed. Its still clean and smells normal 10k miles later. If the clutch in the tranny was whore out, wouldnt it slip all the time not just 1 day and not the next or shift perfect and then the next shift not? Also why if you disconnect the battery for abit does it shift perfect for the next acouple days? thats what makes me believe its not worn clutchs.

I checked the engine and tranny codes today, came up that everything was fine

when you reset the battery it jacks up the line pressure for a bit while it "relearns". By nature of design a clutch slips as it engages. With everything operating normal the slip is minimal. when fluid gets hot, the clutches wear out, or line pressure drops, slippage increases.

 

[1.8laser90]

why would it do it and not do it while driving? lets say i drive it for 20 minutes and the whole time it slips from 2nd to 3rd. Then all of a sudden it doesnt do it the next 20 minutes. this is all stop and go driving also. this is just an example of how it is sometimes. Thats a clutch or band?

 

[HighPSI TSi Guy]

why would it do it and not do it while driving? lets say i drive it for 20 minutes and the whole time it slips from 2nd to 3rd. Then all of a sudden it doesnt do it the next 20 minutes. this is all stop and go driving also. this is just an example of how it is sometimes. Thats a clutch or band?

already been answered.

when fluid gets hot, the clutches wear out, or line pressure drops, slippage increases.

 

[spoolamatic]

I would atlest check the end clutches as they are used in 3rd. gear also and are easy to take off and inspect .I woul suspect that this trany was setting
around for a while and the seal rings might be a litttle hard and not sealing good all the time. The other poster is right ,the trans has three shift trim
that it uses and learns like fuel trims .