The car ran reliably until recently. Then my White 1985 244 automatic stopped running at all.

Trouble began when We put in a radio. A previous owner had something against radio and antenna wiring, and had removed all of it. My buddy used to install car stereos for a living and managed to get a junkyard deck installed and sounding great. Maybe it was a coincidence, but the car stopped running. Two weekends of fiddling around and checking obvious things didn't help. We have confirmed that the fuel pumps are pumping, the spark plugs are sparking,and the motor is cranking away. But not even a cough. Holding a screwdriver on the injectors to feel for the pulses when cranking, I feel none. In my 245, I can distinctly feel the injectors pulsing with this trick, and that car runs. How can I get the injectors on the 244 to squirt again? Any advice appreciated.