I'm thinkin bout tryin a replacement ecm to fix my problem, however, what is the compatibility requirements for the ecm's? Does it have to be the same year, engine and tranny or what? Do I have to have the replacement re-flashed anyways? I was told by a buddy they may have the vin # encoded on each ECM? And what if I just get the stock ECM re-flashed, round abouts how much that could cost?