I know that the 2004 ecu could be swapped over with no problems, but the 05 couldn't due to different pin outs i think.

The issue I have is, I'm replacing my old 2004 ecu (ECUTEK'd) with a standard ECU of the same year - BUT i think i read somewhere that the 04 STi ecu had two revisions, the earlier rev. compatible with a 03 and the latter with a 05 (but not a 03).

Since iv sold the tek'd ecu. Iv acquired another standard one to run in the meantime of my buildup.

I have the ecu chassis and board codes & i need someones help to double check for me:

HC445 10E17, or 112031-7070

if anyone knows...

Don't mix WRX and STI ecu's... as there are different components on the mainboards.

WRX <-> STI not same same

they are both STi ecu's, just not sure which revision the 04 STI ecu is

OK - so I found the right ecu - and put it in.

Now my car wont start coz of the key coding.
Is there anyway I can recode the keys at home - without having to tow my car to subaru ??

pm me if needed

note - there is no way around it. Subaru are the only ones with the computer to code the ecu to key.
all good.

thats what they would like you to believe