1990 Cadillac Fleetwood fuel injection

Should have included the fuel pressure is a steady 39 pounds thru the pressure regulator and will climb to 45 pounds if I remove vacuum from the pressure regulator, that should be the norm for starting the engine cold.

Also I did reconnect the a and b connectors of the adl and set timing to 10 degrees so that was working, after removing the jumper the timing advanced higher to match RPM. Have removed and replaced timing gear cover etc checked cam and crank for timing mark alignment and it was fine also cylinder was at tdc.
Thanks

I have removed all 8 injectors, yesterday and here is what I did to test them,
i used a 7/16 neoprene fuel line hose that fits the injector fuel inlet very tightly, attached to the other end was a 1/4 nippel that screwed into the hose (air compressor quick connect), both ends also had a worm screw hose clamp tightened to be sure of no leak, all that was left to do was set the air pressure regulator from the compressor to 39 pounds that matched exactly the fuel pump pressure from the cadillac, I then filled the tube and hose that are connected to the fuel injector with penetrating oil till it overflowed I then wiped all excess off, I then pluged in the air supply, all was fine no leak, placed a nice clean sheet of test paper down, then connected negative feed ground to right side pin coming from injector, then touched left side pin which is the 12 volt feed for all injectors to a 12 volt source for a 1/2 second at a time, of 8 injectors all but 1 sprayed a nice clean pattern 1 failed with no pattern at all and was replaced, but from my understanding, it seems that 12 volt should be present always at all the left side pins of all fuel injectors, and that either the ecm or bcm which ever controls the injectors is failing to make the necessary momentary closure to ground to close the circuit that fires that particular injector.
Thanks
bob