Auto gear changes confused?

[Jezzza]

Hi guys,

Im not sure really how to describe this issue, but the best way I can is that my gear changes seem to be confused and cant decide to change or not
A little bit of history.. I recently changed the gearbox oil with Mitsu specified oil. I did the full flush which took around 9.5L. The gear changes before the oil change were smooth (about a .5-1 sec delay to change gear between the light on my dash > going from gear 2 to 3 > and the physical gear change in the box)
During this time, the battery had been disconnected a few times for a few days, so I assume the ecu reset?
Does it have to "re-learn"?
How long does it take for the ecu to "re-learn"?

After the oil change, I test drove the car, and noticed that the gear changes were smooth. The gear changes had the same delay, where the light would change from 2 to 3, but the physical change would be a bit delayed.
...But now there is an issue that the physical gear change would spike in revs (only about 300rpm, then drop revs like it changed gear (but hadnt) then respike up by about 500-600rpm, causing the car to do a jerking/jolting motion.
I can negate this by watching the light change, then easing off the accelerator.. and I will get a smooth change

It was slightly over filled, so I have emptied it and its sitting in the correct range when HOT. I had the same issue though.

Now I have only driven the car around 10 mins at a time, and only about 3 times now

I have disconnected my battery in hopes that the ecu will reset itself to "learn"

Any ideas?

Edit: Not sure if this is relating, but the car sometimes will not start first time, or hesitate a bit then the revs kick up (only when first starting in morning)
Just seen some threads about the IACV valve

 

[veegeeta]

If battery been disconnect then it will take a bit of driving around to relearn if you have a good auto box then it should sort itself out, have air con on as well

 

[Guest]

What was the ATF you used?

 

[Jezzza]

I used Diamond ATF-SP III
How long do I have to drive to get the gearbox re-learned?

Hah! Who knew it would be so complicated to check ATF fluid! I will recheck when I get home
https://www.ozvr4.com/threads/checking-automatic-transmission-fluid-level-atf.8376/

 

[Guest]

ATF sounds good. Refer to this previous post I made about relearning the idle and shifting.

 

[Guest]

I notice exactly the same issue with my legnum, except it happens when I disconnect the battery. Its a hesitancy to shift, resulting in a slight spike in revs. I'm guessing its a relearning process which will smooth out over time.

 

[Jezzza]

Ok thanks.
Ill try to take it for a spin over the weekend. Ill just do driving up and down my street without booting it

I always turn the air con off! So will not do it this time haha

Found this too..

On a side note.. why does everyone keep saying the auto boxes need a cooler? If serviced regularly it should be fine??

 

[Jakevr4]

When my car has been sitting for months without being used it does the weird rpm surge and clunk thing.
Last time I thought fuck it of it is going to break anyway I may aswell enjoy the last drive as an auto, went for a very aggressive drive up Mt Tamborine with 20-30 7k rpm WOT shifts and it sorted it's self out.
Only found out reading your post that it has to relearn how to shift haha.

 

[Jezzza]

When my car has been sitting for months without being used it does the weird rpm surge and clunk thing.
Last time I thought fuck it of it is going to break anyway I may aswell enjoy the last drive as an auto, went for a very aggressive drive up Mt Tamborine with 20-30 7k rpm WOT shifts and it sorted it's self out.
Only found out reading your post that it has to relearn how to shift haha.

Not so keen to break my gearbox lol
Im going to try eyeballprawns method first.. if that doesnt work then will try the other method I found

 

[Jezzza]

Ive recet the gearbox ecu and performed the steps above.
Gears change much better! Gear 2 to 3 is still a bit jerky, but not nearly as bad!
I also reset the idle etc. and idle no longer hunts! Very steady idle at 700 rpm