Intermittent Operation Check
- Connect spark tester to 2 different spark plug wires. If no spark, perform IGNITION SYSTEM CHECK . If spark on either or both wires, check for dwell increase from low to high RPM.
- Check pick-up coil and Hall Effect switch (if equipped). Replace, if faulty. If pick-up coil and Hall Effect switch are good and dwell did not increase, replace HEI-EST module. If good, but dwell did increase, check fuel system spark plug wires, distributor cap and plugs.