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View Full Version : Latest cax for LC 12156, cant figure it out



acomp917
February 14th, 2010, 05:22 PM
Hello All,

At the moment I have a 12212156 w/2002 tune(silverado 5.3). I learned how to use cax files. It looks like LC is included in the PCM and build102. I don't think setting the tables worked. Do I need a cax? which one? I did find a collection that is just for LC enable. Says "go to b9000, set "enable", full flash PCM". Then tables will work.

Also, It appears that the transient fueling is also now included in build102. There are cax files for these too. The cax files have more TF tables. Is there any advantage to using the cax, can that even be done?

Gets kinda confusing. The evolution of the cax's are difficult for a noob to follow.

TIA,
S

PS, The brains behind this dev are over the top. I wish I had 1/10th of that capability.:cheers:

joecar
February 14th, 2010, 11:04 PM
Without the LC cax file (which has table B9100), lean cruise will not work on North American PCM's... so as you have discovered, you need the 12212156 LC .cax file contents to be able to run LC.


TF is now included, so you don't need the TF .cax file contents for this anymore.

acomp917
February 15th, 2010, 03:44 AM
Thanks joecar,

Don't want to bother you. Is the latest LC cax just the b9000 "enable" table. That is the simplest one. I just don't know if I am missing something.

S

joecar
February 15th, 2010, 03:54 AM
Yes, B9100 LC Enable... and then you have to edit the other LC tables (B3634-B3639, B3646).

acomp917
February 15th, 2010, 05:16 AM
Hey joe,

Having a little trouble with the LC patch. I have my latest file patched with the LC cax(attached below). I did a tune flash(full flash NA, maybe you can tell me what is required). I re-read the pcm info and the patch area shows "disabled". Tried this twice.

Can you offer any more help? It is good of you to help. Many others will not take the time.


TIA,
S

acomp917
February 15th, 2010, 05:38 AM
joecar,

Thanks for the help. In my haste (it is cold here!), I was opening the prog/file inside and then taking the computer to the trk. In order to get "full flash" I had to start the program with the dongle attached. Now the patch is 'enabled".

I have a personal v1 that I upgraded to v2. Maybe that has something to do with it.

S

acomp917
February 15th, 2010, 11:36 AM
To All,

Lean Cruise works well now. Makes me nervous when the AFR goes +15++ and stays there. Mileage shows up immediately, that is a serious plus. :)

S

Chevy366
February 16th, 2010, 10:47 AM
The LC patch is very useful , have been using it for a few months now and am impressed as well .
First started with a COS3 which was run for 2+ years with no problems , but when I installed a new cam went back to a MAF .tun , just to see what others had to tune with . Decided to see what LC was like and hacked it in the PCM for a go .
What kind of mileage are you seeing now ?

acomp917
February 16th, 2010, 11:21 AM
Chevt366,

Just got everything in order(including system knowledge :) to start tuning in earnest. I have changed the tune from 2k to 2002(think you were part of that). Made radical changes to timing and base VE + PE mode AFR and enable threshold. I changed the tranny shift pressures. I'm thinking about raising the torque limit a little. Will let you know about that mileage when I get the fine tuning done.

As it stands(four rough flashes), the truck is getting about the same mileage, maybe +1 highway, going 16:1+ LC worries me a little. Don't seem to be killin the cats(not as much as I'd like to ;). With the new tune I gotta watch around town... it will burn more fuel if I use it. It is MUCH more fun to drive, is like a mild V8 truck should be... firm and more powerful.

Crazy thing is the 2k tune, the tranny ppm and ratio info was really goofy. I modified the 2002 params in the tune and have been having mixed results. Finally decided to use the EFIL calculator, haven't flashed the latest tune. If I understand correctly, I have my doubts about those mods.

I really like EFIL. Personally, I think it allows access to the goofy thinking and tune that GM uses in their PCM logic.

S

Chevy366
February 17th, 2010, 07:45 AM
Chevt366,

Will let you know about that mileage when I get the fine tuning done.

As it stands(four rough flashes), the truck is getting about the same mileage, maybe +1 highway, going 16:1+ LC worries me a little. Don't seem to be killin the cats(not as much as I'd like to ;). With the new tune I gotta watch around town... it will burn more fuel if I use it. It is MUCH more fun to drive, is like a mild V8 truck should be... firm and more powerful.

Crazy thing is the 2k tune, the tranny ppm and ratio info was really goofy. I modified the 2002 params in the tune and have been having mixed results. Finally decided to use the EFIL calculator, haven't flashed the latest tune. If I understand correctly, I have my doubts about those mods.

I really like EFIL. Personally, I think it allows access to the goofy thinking and tune that GM uses in their PCM logic.

S
Yep , fuel trims (and SRT) have to relearn after each new flash so it takes a few miles to be sure , lol , you can mix and match parameters in tunes , fun to try out different values from different tunes . What does this do ? Oops , well put that back to where it was that didn't work ! :doh2:
16:1 is okay at low loads nothing to worry about , just if you go WOT and you see 16:1 then worry . I like the way LC activates and will hang there even if you do light throttle , enough throttle it will drop out and then go right back in when you level off again . Of course B3647 would do the same thing when properly set .
Enjoy and have fun , tuning is , thanks to EFILive and their descriptions of tables , parameters and what the values do in those tables , rewarding .

GMPX
February 17th, 2010, 09:05 AM
It is a shame GM were forced to remove LC from the E40 and later ECM's, I guess it's a double edged sword, save fuel (good) but increased emissions in LC (bad).

It would be interesting to see which is of more benefit to MPG, LC or AFM.
Consider the cost to GM, LC = about 100 lines of code in the ECM. AFM = lots of mechanical mods and lots of code in the ECM.
What if both picked up 2MPG :doh2:

ScarabEpic22
February 17th, 2010, 03:20 PM
So no chance of E67/E38 LC then?

Hey, I can dream right? :D

GMPX
February 17th, 2010, 04:56 PM
Figured someone would ask :doh:
No chance is the answer, to implement such a thing in to the existing E38/E67 code would send us insane.

ScarabEpic22
February 17th, 2010, 06:36 PM
Figured someone would ask :doh:
No chance is the answer, to implement such a thing in to the existing E38/E67 code would send us insane.

Just have to be that thorn in your side...wont ask again.:doh2: