Purchased my son a 2001 3door s10. It had no motor or trans when i got it. I was sold an engine and pcm that I was told would plug right in and work.well it fire then dies and goes into VATS. (Security mode). Any help to get this truck on the road would be very much appreciated. No obd2 reader works to communicate to computer either. Just spins and spins saying can not connect..