I've had no issues in starting my engine the last 4-5 years, then out of the blue, I'm experiencing inconsistent starts. Make: Chevrolet Model: Impala SS Year: 1964 Engine: 327 Transmission: 3-speed Auto 350 Example: - I'll start the engine cold, runs and idles, no issues. - Turn off the ignition, and attempt a restart, no crank, but all electrical digital readouts appear normal. Battery is reading 12.74 with engine off. Attached is my current wiring diagram, below is my equipment: Mallory Unilte Electronic System Distributor with ECM. Mallory Masterpro Coil Ballast I have performed the following tasks to help troubleshoot the ignition start problem: 1. Battery Voltage checked with engine off: 12.75v 2. Checked all wires for damage & connectivity to battery, starter, solenoid, ignition switch, coil. 3. With the ignition in "On" position (engine off), I placed a test light on the positive side of the coil, and I got no reading (light). 4. Removed cap and rotor, turned ign "on" and ran a voltage check to Negative side of coil: Black voltage meter lead to ground, Red lead to coil Negative. Results: 12+ Volts 5. Ran a "block" photo optics module test, the voltage did not drop to 3 or less volts, so "photo optics" test failed. Additional Info and Questions: - I do have a mallory power spike protector part #29351, my understanding is that this unit is supposed to prevent power spikes, but to what degree, I'm not sure. - Question(s) 1. Should I eliminate (for now) the testing of the starter and solenoid at this time? 2. Can these power spike protector also get damaged, can they be repaired (fuse inside?), and can they be tested. 3. Other suggestions based on these test results?