7 year review of my SMG (from clunk to no clunk)

[Irhase46m3]

Hello Everyone – With the down fall of m3forum.net and a wealth of information lost, I figured I would compile my 7 year experience with my SMG along with some advanced troubleshooting and highlevel discussion about how I fixed my clunk issues.

1. The Clunk- First, its important to understand the SMG is by no means a refined system that you won’t feel it shift. It’s an old RAW system that attempts to operate the clutch based on its limited variables (brake pedal, park brake, engine rpm, abs speed, etc) – This makes a bit unpredictable. Even though it’s a clunky system, clunk is relative. It shouldn’t be making a loud bang or loud clunk when shifting, it should be more of a nudge or thump if the system is operating properly.
2. The right SMG tools – Second, I’ve been using the wrong diagnostic tool to readapt the system. For the longest time I used ISTA/D to initialize and bleed the SMG system. I would think that by following the ISTA/D bleed procedure everything would be fine, yet the clunkyness and hard shifts would continue. I cannot stress enough how important it is to adapt the system with INPA, the bleed and adaptations take only a fraction of the time with INPA and you can feel the transmission/system calibrated way better, specially when launching or flooring it from 0. – Also, reset your engine adaptations via INPA.
3. The rubbers & Joint – Third, I suggest inspecting and changing the transmission mounts, output shaft flex disc, drive shaft bushings and driveshaft CV Joint, these are the main reason for the clunk. While at it, check your tire pressure as well, SMG gets vehicle speed from the ABS sensor.
4. The Air, the VANOS and the valves – Another thing that helped was bleeding my break system, for the longest time I had a tiny air bubble in the break system, bleeding and taking this air out helped with the shifting. My VANOS solenoid was toast which also contributed to hard shifting when at low speeds, replace it with a beefed up beisan solenoid pack. Also, perform a valve adjustment, this keeps the engine running efficiently within spec and this translates into smoother shifting as the output values are within spec for optimal shifting.

The pointers mentioned above helped with my clunk issues and I’ve been clunk free for over a year now. Obviously all of these pointers only work if your SMG pump is operating properly.

The good stuff:
In my venture to try and install an older version of INPA (one that would carry the pump bleed procedure) I started looking at videos online along with downloads that contained older versions of the software. I quickly realized that the new versions carry over the older data, its just more added data for the new chassis/modules. It’s within this concept that I started playing around with the new INPA versions and how its put together (I’m an IT guy) – I quickly figured out that it carries its display GUI menu in a .ini file the file path for the config is located at “C:\EC-APPS\INPA\CFGDAT\” – the .ini we are looking for is inpa.ini (make a copy of the original) – You should be able to double click this file and edit in notepad.

This config file basically gives you a layout of the menu functions of INPA and where the data is located within the folder structure of the OS. At this point you will want to pick and choose which option you want to replace, I replaced E70 for my special tests.

Original inpa.ini file:



Modified inpa.ini file:



Original INPA interactive Menu (you can see its running E70):



New INPA Interactive menu with changed function:



When you hit Shift + F3, special tests pops up and SMG Bleed procedure is now accessible on version 5.0.6 of INPA.



I cannot stress enough that you will need to bleed the system multiple times to get all air out of it, its not a one bleed does it (it never is) – I truly hope this has been informative and helps anyone out there, happy bleeding!

[Johnvu]

Great thread! I have learned so many things over the course of 4 years of owning an SMG. I haven't tried INSTA/D to calibrate the SMG system, only INPA. After reading your thread I am so glad I never went that route because I would have been so pissed lol. The bleeding and calibrations were pretty much the only things that went right the first time when I relocated my SMG system into the drug bin LOL.

[WOLFN8TR]

Very Interesting, thanks for posting!

[TramRam]

I will thank you before reading through what you have entered here!! I've come to believe that us SMG lovers must have something in our DNA that makes for a common thread though all us as a subgroup! No doubt we ALL have had to deal with the haters to some degree or other while going back and forth with the issues that we sometimes have with the system. Where I live, almost everyone who has had SMG has converted to the dark side so NO camaraderie here! In an case, Big thanks!

[992gnt]

I have a question, when bleeding in INPA, should it ever stop purging air? I've bled mine probably a dozen times in the last 6 months, and it always lets off a squeak of air at the end of a cycle. I'm just curious what is "normal" behavior.

[Mspir3d]

I liked DIS a lot more for adapting the smg than INPA. It's a lot more complicated to set up on a laptop though.

[eacmen]

Anyone know how to get INPA to display English instead of german?


Sent from my iPhone using Tapatalk

[Andy2424]

It is very easy.

Find the Inpa.ini and replace the GERMAN in ENGLISH

[Andy2424]

I liked DIS a lot more for adapting the smg than INPA. It's a lot more complicated to set up on a laptop though.

Unfortunately I can't manage it either :-(. It is twice as difficult for me, since everything is described in English. My English is very bad ...

[Irhase46m3]

I have a question, when bleeding in INPA, should it ever stop purging air? I've bled mine probably a dozen times in the last 6 months, and it always lets off a squeak of air at the end of a cycle. I'm just curious what is "normal" behavior.

No air should be coming out of the system. If you have a pump relocation kit then it takes some time to fully bleed the system, i must have had to bleed 24 to 30 times. Its also important that if you are using a vertical pump bracket (as opposed to the horizontal oem position) you will need to bleed the unit in horizontal position to get all the air out before resting it on vertical position with its bracket (hopefully im making sense here) - I have a complete pump relocation kit from burkhart engineering and i came across this issue with their vertical bracket. I wish they would have pointed in their wikipedia as it would have saved me some time.

If you still have air or dont see the bubbles being less frequent, you might have a leak elsewhere in the system or perhaps a bad o-ring/gasket. This all depends on what was done to the system that caused you to bleed it.

hope this info helps!

[Distinct]

No air should be coming out of the system. If you have a pump relocation kit then it takes some time to fully bleed the system, i must have had to bleed 24 to 30 times. Its also important that if you are using a vertical pump bracket (as opposed to the horizontal oem position) you will need to bleed the unit in horizontal position to get all the air out before resting it on vertical position with its bracket (hopefully im making sense here) - I have a complete pump relocation kit from burkhart engineering and i came across this issue with their vertical bracket. I wish they would have pointed in their wikipedia as it would have saved me some time.!

This drove my performance shop crazy having to bleed it so many times and then also discovering that it had to be horizontal in the original configuration.

[HitmanM3]

This is great info, thank you for sharing. My SMG doesn't have any symptoms or issues of concern at this point and I've only done the 40mph + Neutral + press both paddles for 8-10secs. Is there any risk of running thru the bleeding procedure and reset of adaptations on an SMG system that seems to be running normal? If any of the procedures fail can you end up with a non-functioning SMG?

[maw1124]

Great writeup. Thanks. My takeaways are (1) bleeding these systems is difficult and time consuming (check)... I have to think that works better with fresh fluid than sludge (check); (2) chassis rubber needs to be taken care of (check)... sure it’s expensive but no free lunches (or course); and (3) a proper functioning engine and sensors helps (check). The first 2 I’ve taken care of... the 3rd makes too much sense and will have my attention going forward. I’m also paying increased attention to sensors on other cars of this era, so I appreciate its application here.

Cheers,

maw

[Irhase46m3]

This is great info, thank you for sharing. My SMG doesn't have any symptoms or issues of concern at this point and I've only done the 40mph + Neutral + press both paddles for 8-10secs. Is there any risk of running thru the bleeding procedure and reset of adaptations on an SMG system that seems to be running normal? If any of the procedures fail can you end up with a non-functioning SMG?

The reset you are doing is the driver adaptation reset which is when its trying to learn your driving characteristics, which helps slightly and from experience (related to clunks) if there is an issue with the system, the clunks return and its not as smooth.

I've gone through 3 clutches (a recall from ECSTuning) through my 7 year ownership, in learning this system and the mechanics of it, i do all the work myself, you can reset the system as much as you want without causing any issues, the only concern is the clutch curve adaptation which essentially tells the system its a new clutch and it will try to learn it. This will produce a tad bit of a harsher shift as its breaking in the curve.

Its also important to note that within ISTA/D you have access to reset the clutch curve via the SMG module under vehicle tests, when doing this in INPA following the bleeding process (only gives you 3 options followed by F8 to run them) on the third option "full adaptation" it will reset the clutch curve.

In the event that something fails due to adaptation/bleed it will trigger the COG light to be turned on, if you cant complete the whole bleed of the actuator or the clutch cylinder and/or adaptation then there is obviously something wrong with the system that needs attention. At this point you would only be prolonging the inevitable, all systems fail its just a matter of when and do preventive maintenance.

Hope this helps

[992gnt]

No air should be coming out of the system. If you have a pump relocation kit then it takes some time to fully bleed the system, i must have had to bleed 24 to 30 times. Its also important that if you are using a vertical pump bracket (as opposed to the horizontal oem position) you will need to bleed the unit in horizontal position to get all the air out before resting it on vertical position with its bracket (hopefully im making sense here) - I have a complete pump relocation kit from burkhart engineering and i came across this issue with their vertical bracket. I wish they would have pointed in their wikipedia as it would have saved me some time.

If you still have air or dont see the bubbles being less frequent, you might have a leak elsewhere in the system or perhaps a bad o-ring/gasket. This all depends on what was done to the system that caused you to bleed it.

hope this info helps!

Thanks. I bled it as part of the INPA routine, trying to resolve another SMG fault. The pump all related hardware is in the stock location, but it always squeaks at me when it's bleeding.