I can't seem to find an answer to my question which is:
Can I use an 04-05 ecu in my 2003 evo?

I bought the car with an AEM ems v1 and an aftermarket engine and wire tucked chassis harness and I want to go back to totally stock for ease of, really everything.

I keep reading about an "immobilizer problem" but no one ever says what that is or how it is fixed. I assume it's as easy as turning it off or getting the right code to put into a rom maybe?

 

yes you can do it. Head over to the ecuflash subforum and start reading. Its all there.