Tran Fast learn procedure won't work with aftermarket stalls - Any ideas?

[That_guy]

I've been able to do this procedure successfully on STOCK stalled cars, but cannot get this process to complete on any of the cars I've installed a 2800rpm (or higher) stall converter in. I've tried going into the VCM and lowering the idle down, does nothing.

What's the trick to make this work with an aftermarket converter installed?

Thanks

[mbray01]

if anything you may have to raise the idle. The ones i did was not seeing enough input shaft speed because of the converter. If you can get it to learn, you may just have to do it the old fashion way and make a few wot shifts, and no brake decels

[That_guy]

if anything you may have to raise the idle. The ones i did was not seeing enough input shaft speed because of the converter. If you can get it to learn, you may just have to do it the old fashion way and make a few wot shifts, and no brake decels

Thank you for the input sir.

I'd rather try to get this procedure to work first, before trying anything else. Before realizing how important this was we previously hurt a few freshly built 6L80's. Since doing these fast learn procedures we've had no issues.

So you're suggesting raise the idle and re-test?

[mbray01]

thats what i had to do, the loose converter was not spinning input shaft fast enough. was just throwing that slow learn process out as when these trans first came out and the software wasn't correct in the scanners we were being to told by gm engineering to learn the units old school. hold to floor on accel, and do not touch the brake while slowing and allowing to vehicle come to a crawl by itself. anyway, I do believe you are experiencing the same problem I had and the input speed was not sufficient for the tcm to see the rpm drop during the clutch test.

[seven ends]

I couldn't get the fast learn to work on my built 6L80 with triple disk 2800 stall. But connecting to do the trans adapt reset and preset made a huge difference in learning time and I do that after every significant transmission change now. I read elsewhere herein that it forces it to start learning with your new programming because everything else has been cleared.

[HartRod]

I couldn't get the fast learn to work on my built 6L80 with triple disk 2800 stall. But connecting to do the trans adapt reset and preset made a huge difference in learning time and I do that after every significant transmission change now. I read elsewhere herein that it forces it to start learning with your new programming because everything else has been cleared.

What's the procedure for the adapt reset and preset? TIA

[lablkv6z]

Hey guys, this thread pertains to the issue that I am working with right now, so I will add to it, for those who are in the same boat.

Cliff notes: Cammed LS3, 3800 Stall converter, Trans adapt reset/preset/fast learn (failed), Now only forward gear is 4th, that's it.

I'm in the process of tuning my 2008 Corvette A6. I made some changes to the Trans/Torque Management/Upshift/Torque Factor tables and the Trans/Shift Pressures/Adaptive/Oncoming Pressure Preset tables so I figured a trans adapt reset/preset was in order.

I followed the directions in the Fast Learn and Trans Cleaning Sticky: https://forum.hptuners.com/showthrea...ght=fast+learn

After tapping the Adapt reset/Adapt preset/and initiating the Fast learn in the VCM scanner, the function fails while calibrating drive.

I've read that with the higher stall TC?s, the input shaft RPMS aren?t high enough for the testing, which causes the Fast Learn to fail.

So now since I?ve reset the trans adapts, when I put the shifter into Drive, I can see in the scanner that it goes immediately into 4th gear and stays there. It?s the only forward gear I have in Drive.

When I put the shifter into Sport, I can see on the heads up display that when the car isn?t moving, it?s flashing between 2nd and 3rd gear, as soon as I move forward, it goes directly to 4th and stays there.

I've tried adjusting my idle rpms in the tune down to 625rpm and also 1750rpm, and do the Fast Learn but both failed.

I've also reflashed to a completely stock trans tune with the same failed outcome.

I've driven the car for about 100 miles and it still stays in 4th gear.

Any suggestions are welcomed, thank you all.

-T

Car information, 2008 Corvette, 6L80E, Cammotion mild camshaft, boltons, Circle D 3800 multidisc TC

A6 Trans fast learn fail.hpl
vve7 trans reset failed stuck 4th gear.hpl
vve7 trans adjust.hpt
C6 NA graphs.Graphs.xml
C6 NA trans channels.Channels.xml

[Cringer]

The fast learn doesn't work with high stall TC's.

In fact fast learn does not work on all cars in factory trim either (it works as it should in some/most cases, but many have found issues on stock vehicles).

[lablkv6z]

The fast learn doesn't work with high stall TC's.

In fact fast learn does not work on all cars in factory trim either (it works as it should in some/most cases, but many have found issues on stock vehicles).

Thanks for the feedback.

I will try flashing the stock trans tune once again and try clicking the Trans Adapt reset, Trans Adapt preset and see if it will actually go through all of the gears instead of just going straight to 4th.

[alabastarbastard]

I would try using the tech2 software with a VCX NANO from amazon... you can do a lot of functions with this that the hptuners module cannot

goatrope garage has a detailed video on accessing BCM, TCM, canbus operations, clearing and reseting sensors, etc, etc...

search his YT for...Cheap GM ScanTool,

[lablkv6z]

I would try using the tech2 software with a VCX NANO from amazon... you can do a lot of functions with this that the hptuners module cannot

goatrope garage has a detailed video on accessing BCM, TCM, canbus operations, clearing and reseting sensors, etc, etc...

search his YT for...Cheap GM ScanTool,

Thanks for the information. We ended up using one from a buddy at the dealership. When he read it, it stated that the trans tune was stock which was odd. He reflashed the trans tune to stock any ways to try and it was still doing the same thing.

Contacted another locally know tuner and we worked and tried multiple things. Then I set everything in Torque Management back to stock (including the ECM side), and guess what, it shifted like normal again!

So after figuring out it was something in the torque management ECM side, I slowly back tracked, and figured it was one cell that was throwing the trans into the "limp mode".

Engine/Torque Management/General/Traction Control System/Max Torque. This cell is 479 lb ft, I maxed it out and it didn't like it. I found that the highest I could set it was 481, anything higher throws it in "limp mode".

Now even though this is under TCS Method, I find that whenever I am making a pull and it gets to 479 lb ft, the ECM pulls timing/something else and restricts power causing loss of momentum. Trying to work around this and maintain TM.

I've found that this is an issue with the 07/08 6L80E TCMs in the C6s (possibly G8s as well). I'm still open to guidance guys if ya'll have any suggestions. Thanks. BTW I purchased an authentic US GM Tech 2 last night for future use.

-T

[lablkv6z]

Following up, after adjusting the Virtual Torque tables in Beta, all is working as it should now. Thanks guys for the help.