Note On Intermittents

If Code EO12 is stored as a history code, start engine and allow it to idle. Manipulate circuits No. 430 and No. 453. An intermittent open will cause the engine to stumble or stall when PCM looses distributor reference. If wiring and PCM connectors are okay, check HEI pick-up coil leads intermittent open circuit.

Fig 1: PCM Code EO12, Schematic, No Distributor (Tach) Signal

Fig 2: Flow Chart, PCM Code EO12, No Distributor (Tach) Signal