sicksilverado

I have a 96 Silverado thathad a vortec 350 in it. That motor blew so i took aVortec 350 out of a 99 tahoe. They should be the same motor from what im told. The problem is.... it will turn over like it wants to start but wont. Its like its not getting fuel. The fuel pressure is more than good and the motor will run if i dump gas down the intake but it just wont start on its own. Any help on this would be greatly appreciated!!!!

scooter00754

Dont hold me to it but i would say start with the ecm i have herd of them not working when a motor is swaped, just a thought