1988 Chevrolet k1500 350 v8 not getting signal to fuel injectors
So, it's the injector circuit. There is a 10 amp injector fuse in the fuse block, on left side, 4th one down. Check this fuse. It supplies constant power to both injectors, on the red wire to injector 1, and a white wire splice from this to injector 2. A steady 12 volts anytime key is in on, run, or start. You can check this with a test light or voltmeter. Ground the test light and probe injector connector's red wire on injector 1, and the white wire on injector 2-both should be hot with key on.
This may be why the noid light didn't blink. The noid light must have this steady power signal, and when the computer internally grounds the injector ground circuit for a split second, you get injector pulse-or a blinking noid light.
You can check the ground circuit separately with a test light also for each injector. Place the ground clip of test light on the POSITIVE battery post, and probe the blue (ground) wire on injector 1, the engine must be cranking over, and the test light should be blinking. Do the same for the green wire on injector 2. If the test light is blinking on both ground wires, with engine cranking-the ground circuit is good. You are sending power down the ground wire to computer, and when the computer grounds the circuit, the tester will light up-it will blink because the computer only momentarily grounds the circuit to cause pulsing of the injectors.