Gearbox Issues - 7G Plus, please help

[Mercedes.Enthusiast]

Hi all,

I have an ongoing issue with my gearbox (7G plus from a W212 2012) and I'm really puzzled. I hope someone can shed some light on this, would be very much appreciate it.

I have an issue with my gearbox, on cold it jerks, quite badly downhill, up the hill and even road it does but not that bad, on from 1st to 2nd and once gets a bit warm from 2nd to 3rd, all the other gears silky smooth. Also on kick down, it literally gives you two huge jolts, one after another before it actually pulls.

Took my car to a local garage which tested the mechatronic and TCU alongside all solenoids and everything seems to be fine, reinstall all in and changed the oil. Then the car seemed slightly better, then I've reseted the TCU and torque converter lockup and the car got even worse, it jerks even more on cold until heats up. When they removed the oil, apart being a browish colour, everything looked spot-on, no metal inside or anything, even the magnets were clean and no transmission errors whatsoever.

Do you think a torque converter adaption (KUB) would help? And why when I reset the torque converter lockup, the gearbox perform even worse? Does it look like there's a gearbox mechanical issue?

I've read somewhere that I can disable the lockup to test if the gearbox improves but not sure how safe this is. It also had software updated with no improvement whatsoever.

Could anyone help, please? I'm willing to pay anyone knowledgeable as I'm completely fed up with this issue and not sure what else to do.

Thanks a lot and hopefully someone can help me out tracking this issue down and get it fixed.

 

[rifiki]

I would get the codes read by indie with STAR

 

[Mercedes.Enthusiast]

I would get the codes read by indie with STAR

There're no errors at all. The gearbox and engine are completely error free. There have been read multiple times and never had errors.

 

[star]

Now you have reset the adaptations, you need to re teach them. It might also need a software update.

 

[Mercedes.Enthusiast]

Now you have reset the adaptations, you need to re teach them. It might also need a software update.

Thanks a lot for your valuable input. Well it had a software update, the latest one. As for the reteach them, is it possible without Star? This is caused by the gearbox adaptions or the torque converter lockup adaptions?

Thanks a lot, really much appreciate it.

 

[ajlsl600]

i stand to be corrected,but believe that if you had an update (and i hate the whole idea of such a requirement ) you may have to drive it around for a while to get it to (re learn yr driving and preferences) . again that i dont believe to be a "star" issue ,but one of driving around for a while in a normal manner. i await correction.

 

[Mercedes.Enthusiast]

i stand to be corrected,but believe that if you had an update (and i hate the whole idea of such a requirement ) you may have to drive it around for a while to get it to (re learn yr driving and preferences) . again that i dont believe to be a "star" issue ,but one of driving around for a while in a normal manner. i await correction.

Well I drove it already for about 1 hour and then some short journeys and it's exactly the same. I do believe I need to re-adapt the torque converter lockup but what I don't really get is the fact why when you reset the torque converter and gearbox adaptions, you need to re-learn them, why they are not like a new car? That's a bit of confusion for me, however, is there any way for me to re-adapt the gears and torque converter without star? Also, if I disable the torque converter lockup to see if it still jerks/jolts, would be a good or bad idea?

Thanks a lot

 

[ajlsl600]

dont know if this can help ?

https://www.google.com/search?clien...ner+after+a+gearbox+software+update#kpvalbx=1

 

[star]

You have made it worse by clearing ALL the adaptations, it’ll take more than driving for an hour to relearn.

 

[Mercedes.Enthusiast]

dont know if this can help ?

https://www.google.com/search?clien...ner+after+a+gearbox+software+update#kpvalbx=1

The software update has been done prior of changing the solenoids and redo the service for the gearbox. Then I've reset the gearbox and torque converter adaptions. I've done what the video shows but before resetting the adaptions and not much of a change, the jerks and jolt still there, however after reset they're a bit more aggressive.

You have made it worse by clearing ALL the adaptations, it’ll take more than driving for an hour to relearn.

What would be your advise? What should I do in this instance? I'm not entirely sure why once you reset the adaptions it doesn't revert back to factory adaptions meaning it should be like new. This is a bit awkward, anyhow, do I need to relearn the gears or the torque converter?

Thank you.

 

[LostKiwi]

I believe (and Ian please correct me if I'm wrong) factory adaptations are for a brand new unworn box. Yours has been used so will have some wear so the factory adaptations will be incorrect.
Using Star will allow the ECU to test various components and set new parameters that take account of the wear present.

 

[star]

Yes you have set it to factory adaptations, which might be ok for a new box BUT your box isn’t new. I would take the car out with a star connected and adapt the box and torque converter. Even this takes time and and a empty/quiet road.

 

[Mercedes.Enthusiast]

Yes you have set it to factory adaptations, which might be ok for a new box BUT your box isn’t new. I would take the car out with a star connected and adapt the box and torque converter. Even this takes time and and a empty/quiet road.

I've been told by other garages this sounds like a torque converter issue more than adaptions. They claim factory adaptions will be reset to learn your driving style but if it does jolt and jerk then sounds like torque converter issue. Do you think torque converter might be the fault?

 

[star]

Difficult to say over the net, might have been better to have had a road test done before you reset stuff.

 

[Mercedes.Enthusiast]

Difficult to say over the net, might have been better to have had a road test done before you reset stuff.

I did road test it and it was slightly better but still could have felt the gear changes between 1 -2 and 2 - 3, more noticeable in 1 - 2. Then decided to do the reset to see if actually sorts it out but unfortunately it didn't. Any idea how should I know if the torque converter is on its way out? Thanks a lot

 

[Botus]

You have made it worse by clearing ALL the adaptations, it’ll take more than driving for an hour to relearn.

wiping out the adaptions wrecks it.... you weren't supposed to mess about with them - STAR's post are spot on

 

[ajlsl600]

out of some interest ,what goes on during the learning process then, which i thought was an ongoing situation unless everything has been disconected