Gen1 Speed 3 ECM / ECU Compatibility issues, help please.

Tried to search first but to no avail. Looong story short, my 2008 speed3 is at the dealer and just had it's 2 wiring harnesses replaced. There is now a code (still awaiting further info from the dealership) that they are blaming on a mystery wire coming out of the ecu (an old post in the original forums, that cannot find). They said connecting the mystery wire to the new harness "might" fix the code but that they were not sure nor could they do that without voiding their warranty.

I would like to get my hands on a replacement ecm / ecu, to see if that will help resolve the problem/code while in their hands, so that I can walk with a warranty. According to my vin I was told I need part # LKZ8-18-881. I cannot for the life of me find an affordable replacement with that exact number. I have however found a bunch on ebay under $100 but there seems to be every variation of the part 3 except mine.

Which, if any can be used as a replacement? Can they just flash any of them over to match your vin/model/trim or do I have to find the exact part number?

Thank anyone in advance for any insight, this has been a complete nightmare. This all started with what was supposed to a "routine job" replacing the turbo... got the car back hesitating and jerking.

Edit: If there is a better place to post this, where it will get better exposure, please let me know. I am a mess over this whole thing, the car has been there for like 8 months with my turbo warranty wasting away by the day.

 

If you do a part lookup at the dealer it should tell you what other part numbers are suitable replacements. Many of those other SKU s are the same just a different supplier or inconsequential other change

 

Thank you Easter Bunny. Found a dealer that was willing to spend the time.

I doubt this will help many people, unless they have the same computer part number but:
2008 MS3 GT
OEM ECM PART NUMBER
LKZ8-18-881
COMPATIBLE VARIATIONS:
L34C-18-881G
L39S-18-881
L39S-18-881A
L39S-18-881C
L39S-18-881D
L39S-18-881E