1996 Ford Escort Won't start

I replaced the 1.9 engine with a used engine. It initially started and ran excellant. I drove it and it later started to idle poorly. When I turned it off it would not start back up. I later noticed that the camshaft position sensor connector was not plugged in. Also I neglected to plug in the exhaust lines from the EGR tube that went to a sesnor on the firewall. I corrected both. Still won't start. I have 120 lbs compression all cylinders. All plugs firing. All injectors pulsing. Good fuel pressure. I pulled the IAC and plugged the hole with my finger. Good vacuum. I suspect the computer is not firing the plugs or the injectors at the right time. Normal cranking speed I tried disconnecting the battery for eight hours to reset the computer. No joy. Help please!