View Full Version : 2018 L83 5.3 Install
Mark B1
March 6th, 2021, 09:33 AM
I have installed a 2018 L83 Chevrolet 5.3 V8 and 6L80E transmission in my 2013 Jeep Wrangler. All is working well however the state I am in requires the Jeep Vin to show in the GM computer for emissions. Is this possible to change with EFI Live and if so what version would I need to change the 2018 computer.
minytrker
March 8th, 2021, 02:37 AM
As far as I know you cant change the vin in a E92 ECM and make it stay. Dont know anyone who has done it.
Mark B1
March 8th, 2021, 04:14 AM
Thanks for the response. I can get it thru without changing the vin it just takes a lot more steps. Everything for emissions is here just this state wants to see the original VIN for testing.
GMPX
March 8th, 2021, 09:13 AM
As far as I know you cant change the vin in a E92 ECM and make it stay. Dont know anyone who has done it.
That isn't correct, VIN change on the E92 works just fine. Often people get caught out on bench harness setups or conversions where they don't use an IGN +12V input and they switch battery power as well so when they turn off power the ECM loses all power.
The actual VIN change is committed to flash when the ECM is shutting down, not when the commands are sent. So if your power setup isn't correct (again assuming on a bench) then the VIN will never be updated in the flash memory.
Mark B1
March 8th, 2021, 10:43 AM
Shure would make things easier if he vin change will work. Engine is running fine on the stock GM tune I just need to change the VIN for less questions at emissions.
In-Tech
March 8th, 2021, 04:04 PM
Some e38's, e67's, e78's, e92's, probably others, require a specific strategy for VIN change. After a calibration change or whatever. Key off for 30 seconds, key on and clear DTC's, DO NOT cycle the key, leave key on after DTC clear, then do a vin change and it will stick after key cycle. It has something to do with the internal "housekeeping". This procedure has worked for me every time.
minytrker
March 8th, 2021, 05:46 PM
That isn't correct, VIN change on the E92 works just fine. Often people get caught out on bench harness setups or conversions where they don't use an IGN +12V input and they switch battery power as well so when they turn off power the ECM loses all power.
The actual VIN change is committed to flash when the ECM is shutting down, not when the commands are sent. So if your power setup isn't correct (again assuming on a bench) then the VIN will never be updated in the flash memory.
I'll give it another try. The last E92 I tried changing the VN did not work, it would act like it changed but if you read out the tune again the old vin would be there. I have changed hundreds of VIN's on ls1b, e38, e40 and e67 with no issues.
GMPX
March 8th, 2021, 07:25 PM
Ok I can see the confusion, the problem is the ECM keeps multiple copies of the VIN (I think the E92 stores it in 4 different locations and sometimes they are different), when you load a tune file EFILive is looking at one specific location but that might not be the active VIN. When the VIN is being requested via a Scantool the ECM knows which is the most recent (and active) VIN and sends that back. I am sure if you'd rechecked it on the scanner rather than reading the file back out it would have changed.
minytrker
March 9th, 2021, 03:01 AM
Ok I can see the confusion, the problem is the ECM keeps multiple copies of the VIN (I think the E92 stores it in 4 different locations and sometimes they are different), when you load a tune file EFILive is looking at one specific location but that might not be the active VIN. When the VIN is being requested via a Scantool the ECM knows which is the most recent (and active) VIN and sends that back. I am sure if you'd rechecked it on the scanner rather than reading the file back out it would have changed.
With it storing vin in multiple places is efi live changing it in all of them? I sell hundreds of used ecm's and flash them based on VIN (similar to SPS) to make them the correct vehicle (if its a factory vehicle and not a swap) then I read out with with efi or hpt and make changes. If its a factory vehile will changing the vin with efi live make all the modules happy. The last factory 2016 I did, I coudnt get the VIN to change in ecm so I changed the vin in all the other modules to match the ecm because the different vin in ecm made alot of modules unhappy. (Please check your PM)
GMPX
March 9th, 2021, 09:42 AM
The multiple copies of the VIN stored in the flash cannot be changed by a scantool, the ECM will update them itself.
But I think you might still be a bit confused though, when you change the VIN via the scantool the ECM updates the 'RAM' copy of the VIN, this is the same copy that is sent back to a scantool and other modules on the bus.
When the ECM is powered down it will then update the copies of the VIN in the flash memory with the VIN stored in 'RAM' and flags which copy is to be used, but the copies of the VIN in flash are also split into two sections (one is just a back up).
Then when the ECM is powered back up it knows to copy the VIN stored at say slot #2 back into RAM, again the RAM copy is what will be reported to other modules and to a scantool.
If you were to read the ECM then the VIN that EFILive shows might not actually be the currently active copy the ECM is using, there is no way around that though which is why if you want to make sure the VIN took when it was changed just used the F4: OBD-II info option and the VIN sent back from the ECM using that method is the one in use.
joecar
March 10th, 2021, 12:42 AM
"When ECM is powered down..."
This is BATT/12V and not IGN/SW...?
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