No spark fault. No error codes

I have a 2003 sunfire with a 2.2 ecotech that has a no spark condition. It cranks but doesn't start, even with starter fluid, and gets no spark on head. Traced back problem. Ignition coil reads same resistance as my sister's working cobalt. Swapped ICU with junkyard unit. Have power and ground into icu, but no aparrent signal from ecu using a check light and multimeter. Replaced ecu with junkyard unit and replaced crank sensor. No obi2 codes