gm os to custom os

[69camaro5speed]

i was looking over the custom operating systems trying to figure out what matches my gm operating system my stock one is 12216125 i dont see a custom one that matches mine or maybe i havent figured it probly more like it anyone know what custom operating system matches that looking for sd 1 bar system its a 2002 8.1 avalanch need to figure this out so i can test this weekend trying to lurn the custom operating system on my stuff have a twin turbo motor coming up to do any help would be great thanks

[GMPX]

That one was never converted into a 2bar O.S because it was only used on flex fuel (E85) trucks, for some reason, not many folks want to boost these!!.
Anyway, if you are not running the flex fuel thing then you can find another 2002 O.S that we have done that was used with that motor.
Off the top of my head I am not sure which ones they are, but I'm sure someone else will chime in.

Cheers
Ross

[1SlowHoe]

That one was never converted into a 2bar O.S because it was only used on flex fuel (E85) trucks, for some reason, not many folks want to boost these!!.
Anyway, if you are not running the flex fuel thing then you can find another 2002 O.S that we have done that was used with that motor.
Off the top of my head I am not sure which ones they are, but I'm sure someone else will chime in.

Cheers
Ross

So if I know I will never run E85 (and I wont) I can use another 2002 OS? Such as??? You wouldn't happen to know where I could find a 2002 (512kb) OS that has a 6.0L and a 4L80E already in one file? I run the 12216125 OS currently and cannot find a OS with a 4L80E in it. I am about to complete an 80E swap into my Tahoe and I'm not sure there is an OS out there that will let me run it

[joecar]

I would say do this (and let anyone correct me):

Find a 12212156 OS that is used on a vehicle with a 4L80E.
Then copy all the tables (table-by-table) from your 12216125 to 12212156.
Flash in your new 12212156 and see if your truck runs and shifts.
If it does, then follow the COS tutorial to upgrade to COS5.

[joecar]

From www.holdencrazy.com here is an 12212156 OS running an 4L80E (I "annotated" the filename so I could remember the trans)...

[1SlowHoe]

What about OS 12208322? It seems to have everything I need 6L, 4L80, traction control, and Electronic Throttle Body. It is from a 2001 3/4 ton 2500 Silverado 4X4.
My Tahoe is 2WD but I don't see how that should matter.
So, all I need to do is copy every table from my current tune to the new OS (one at a time ) and leave the transmission segment alone, correct?
What would upgrading to COS5 do?

[joecar]

What about OS 12208322? It seems to have everything I need 6L, 4L80, traction control, and Electronic Throttle Body. It is from a 2001 3/4 ton 2500 Silverado 4X4.
My Tahoe is 2WD but I don't see how that should matter.
So, all I need to do is copy every table from my current tune to the new OS (one at a time ) and leave the transmission segment alone, correct?
What would upgrading to COS5 do?

You could try 12208322, but you can't then jump to COS5 from there;
COS5 has boost/nitrous tables, and a TP-vs-RPM VE table in case you want a big cam;

yes copy all tables, table-by-table, including the transmission tables;

it's the transmission "segment" (which contains the tables you see and other "stuff") that must match the transmission;
so whatever you copy "from" -> "to", the 4L80E segment must end up in the "to".

[1SlowHoe]

You could try 12208322, but you can't then jump to COS5 from there;
COS5 has boost/nitrous tables, and a TP-vs-RPM VE table in case you want a big cam;

yes copy all tables, table-by-table, including the transmission tables;

it's the transmission "segment" (which contains the tables you see and other "stuff") that must match the transmission;
so whatever you copy "from" -> "to", the 4L80E segment must end up in the "to".

I think I get what you are saying.
I take the OS that was built for a 6L/4L80E and use that as my new OS. I then manually copy all of my "non-Transmission related" tables from my current OS into the new OS with the 4L80E built into it. So now all my fueling, PE, VE etc... tables are in a tune that runs a 4L80E transmission.
Am I close?

Another question. I remember once playing with the tuner and was going to do a complete reflash and it warned about doing it throught the ODB port. It recommended that I use a bench harness, which I don't have. Do many people reflash the PCM with a new OS with no issues or is it a risky thing to do?

[1SlowHoe]

I am at a loss. The PCM acts as if it is seeing 0 TPS movment. The truck will not idle unless I push the gas. If I floor it I will see about 2000rpm and the truck will barely move. It feels as if its in reduced power but I dont get that DTC or message center light. If I flash the original tune in, which runs the 65E, everything is fine. The throttle tachs right up and idles great. Of course I didnt try to drive it because of the transmission file differences. Whatever it is, it is in this tune.
The only thing I can think of is the VIN is not the same in the new file and thats an issue. But if it were a security thing it shouldnt run at all right? Or, this OS requires different voltage signals to the TPS. This OS I am using is from a 2001 HD Silverado.
I have attached a couple of logs and the tunes. Ignore the AFR, I didnt have that hooked up except for the last log named 80E3.
Please help
LOGS:
80E1 is a startup log and holding the pedal to keep it alive. Ignore AFR.
80E2 is a startup log and holding the pedal to keep it alive. Ignore AFR. Different PID selection
80E3 is the same but with the AFR reading.
TUNES:
Chris 02 HO is my 65E dyno tune that works well
Working 80E file_Improved is the file that is in the truck and the logs were made from.

[1SlowHoe]

Every one. My TPS % sits at 0 even when I floor the gas
I load my old 4L65E tune and it revs right up if I press the pedal.