1. Check for 8-9.5 volts on the Orange wire at the distributor pick-up connector.
2. If 8-9.5 volts is present on the Orange wire, unplug the Manifold Absolute Pressure (MAP) sensor.
3. Check the Violet/White wire for 5 volts.
4. If the 5-volts reference is OK now, replace the MAP sensor.
5. If still no 5 volts, snip the Violet/White wire near the PCM at pin 6.
6. Check for 5 volts on the snipped wire out of the PCM.
7. If still no 5 volts, check the power supplies at the PCM on the Red wire at pin 3 and the Dark Blue wire at pin 9.
8. If the power supplies are OK, the PCM is faulty.