E46M3 Clutch slur induced by factory SW flash

E46M3 Clutch slur induced by factory SW flash

Author
Discussion

Davidonly

Original Poster:

1,080 posts

192 months

Sunday 23rd April 2017
quotequote all
Hi all

after putting it off for a while the discovery that SMG software could be up-rated by going to the 2007 release (mine is a 2004 car) without effecting Mondial warranty I went ahead with it. I had hesitated as I do believe in if it ain't broke don't fix it with some things! Anyway the indy I now use had my car for suspension re-fresh so I decided to get the latest S/W into the SMG. The benefits included (apparently) improved downshift rev match and 'better drive'. The only problem I ever had was occasional pick up shudder when cold - so perhaps the 2007 flash would sort that??

As it turned out the DME was also flashed which made sense as they kinda match up apparently. So now I have the latest factory (but NOT CSL) DME and SMG software flashed onto my car.

RESULT:

Clutch slur frown

Unfortunately my favoured option of going back to 'as was' is not available to me (they didn't / can't keep the old flash).

Obviously very disappointing as previously the gear change was positive / fun in all modes on flat or feathered throttle before the 'up-grade'....I have also learned to heel and toe the downshifts so that wasn't really a problem for me. SO I feel pretty stupid now having ruined my car ....

Car has warranty but would rather resolve this with the garage concerned than resort to main dealer at this stage (it is after all 'self inflicted')!

Now what??

Internet search seems to say I have joined a large group of people trying endless 'fixes' to eradicate this fault.... Can it be done?? It all worked before (like a few days ago) so it MUST be possible.

HELP!

helix402

7,832 posts

181 months

mark.c

1,090 posts

179 months

Sunday 23rd April 2017
quotequote all
I used this as a guide and it sorted a slowly developing slur on my CSL brought on by an increase in town driving :

"Put in sport mode, warm up car and do a few redline pulls in each gear, then off sport mode and do medium load gear changes ... lastly put it in slow shift and do some carpark plodding around type gear changes so the system can learn and re-adapt. Repeat a couple of times and see if it improves. "

Plus it's free smile

Diablo85

1,561 posts

142 months

Monday 24th April 2017
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Hi David

Seems there might be a mismatch between your old adapted values and the new software update.

You can try as Mark suggested to see if it improves, otherwise you'll want to explore a full SMG calibration (reset) as I did:

http://forums.m3cutters.co.uk/showpost.php?p=12308...

This will fix it for sure, but the garage needs the dealer type tools (GT1 or Autologic) - ask them first.

Finally, while this solution works, the problem can creep up again for some. I learned from another owner that driving around town speeds in S5 for a long time can induce it, thus revert to S3/S4 for town driving, and use S5/S6 for the back roads. Following that advice after the SMG reset procdeure, the clutch slur never returned in my 4 years of ownership.

smile

GregorFuk

563 posts

199 months

Monday 24th April 2017
quotequote all
If slur becomes an issue you really only need to do two things. Re-teach the clutch curve and bite point. Make sure to do it with the gearbox fully up to temp.

Davidonly

Original Poster:

1,080 posts

192 months

Tuesday 25th April 2017
quotequote all
Thanks for the replies so far. It's not adapting (the garage asked I drive it and see if it learns on its own) so I'm taking it back for adaptation / calibration. I now suspect that the new software is going to be less aggressive than the old - I was after better downshifts - not a reduction in that razor sharp gear change. Overall not my most well thought out decision!

Having dug around on www seems to be a common problem - with some people resorting to magic to cure it... It is not always as simple as re-setting the software.. Hopefully I'll get lucky.

Some conflict on the temperature for re-set. Some say hot some say stone cold.

Mines been spot on for the 87000 miles I have driven it (it had a new clutch due to DMF failure at 50k and that was perfect after installation) with no slur no matter how hard or soft I drove it with either clutch. It has had a few pickup shudders but I was living with that as the open road experience was always superb.

This is a real bummer as it really spoils the 'feel' of the machinery when pressing on.

Got some time is Scotland end of May- really keen to have it sorted by then.

Having just had the suspension done I'm now thinking crazy thoughts. If this can't be sorted the car will have to go frown






mwstewart

7,554 posts

187 months

Wednesday 26th April 2017
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It needs to be hot i.e. the operating temperature of the gearbox. Running the procedure on a cold gearbox with different tolerances to a gearbox at operating temp makes little sense.

SebringMan

1,773 posts

185 months

Wednesday 26th April 2017
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Do you have an INPA/DIS lead that can flash the modules?

You *may* be in luck ; WinKFP with the SMG data files has old versions as well as new versions. But it seems that the adaptations need to be done correctly first.

I know what you mean about the heel and toeing aspect of the SMG. I did like that. However the CSL shifting has convinced me otherwise ; it was like I was driving another car after I carried that out smile.

Davidonly

Original Poster:

1,080 posts

192 months

Thursday 27th April 2017
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so....

adaptation / bite point and clutch curves re-set. System hot. And its back to normal smile

I await a cold start test to make sure that it doesn't do crazy things like re-adapt (badly) when it gets going again after standing overnight etc.

Re CSL DME and SMG flash. Yes I am thinking about it. However car still has Mondial Warranty and a rattly vanos frown

Apparently it's not bad and probably not needing replacement so I'm keeping things 'stock' and the warranty running until I either get a new VANOS or get the mod work done (a place in Darlington does it). Once the VANOS is sorted I think I'll drop the (monthly) warranty and get the shells done plus maybe some subtle mods (like CSL rev match).

Thanks to all for your input. Hopefully chapter closed soon (after a few drive cycles).

smile

mark.c

1,090 posts

179 months

Thursday 27th April 2017
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Great news. Enjoy smile