don't know much about the 3k's but seems like your going about everything in the right way. ecu definitly sounds fried IMO. mine did the same thing. both times and you said "It cranked but just would not turn over..all i get is the sound of wanting to start but never does" so is it actually turning over and not starting? or just not doing anything?. and if its doing the same thing with another ecu i would start with the crank and cam sensor.