I own a 1987 Z-28, 5.0L 305-v8, have replaced all sensors and the computer. The engine seems to run fine. The car has a voltage/electrical type problem. No codes in computer, no codes on diagnostics machine, and have been told that the alternator was okay. It lopes at idle, and at speed. I have replaced almost everything for the timing, and still cannot solve this problem. The car dies and when tried to be restarted, no electrical power. I checked gauges for shorts, nothing. The starter is fine, and does not appear to be bad. I have replaced the command module, distributor-twice now. Anyone with any ideas to find a solution, please help. The battery has been drained once, and charged...still the problem remains.