I have a 1997 silverado c1500 5.7 2wd I have literally changed every part related to spark for this truck I ran a multimeter and a test light and a scan tool on it and still can't find an issue the only things I haven't tried changing yet are the wire harness and the pcm I have a 96 model as well that is somewhat of a donor truck since the transmission went out in it . The multimeter had a voltage of 10 when key was turned and would drop to 8 while cranking on the crank sensor the camshaft sensor the ignition control module and the ignition coil I tested to see if the ignition switch was bad as well and it checked out fine please help me get to the bottom of this! Thank you!!