Fuel Injector Problems 1995 Blazer

I am working on a 95 Chevy Blazer. Fuel injectors and housing appear to be clear and in working order, but I'm only getting fuel out of one side (3 of 6 injectors). Any suggestions???

Either the wiring harness to the injector body is screwy or the fuel injector itself is bad.

Someone on another forum had this issue and only replacing the injector spider fixed it; his wiring harness apparently tested fine.

How are you checking for fuel on one side?