You need to  access the OE website and possibly buy a subscription and perform it using an OE program downloaded and performed off a windows laptop. Non Dealer Programming options might only be available for certain modules 

 I don't think that ecm is new at all, being that is such an old car, rebuilt at best, which means it does not need to be flashed, the software is in it. if you can read data with all the pids then its not new. go to immobilizer and hit pcm replacement, that should do it.