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Home >> GMC >> 1983 >> Forward Control 6.2 J, Standard >> Repair and Diagnosis >> Engine Performance >> Ignition System - HEI >> Testing >> Intermittent System Problems
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Intermittent System Problems

  1. Using a spark tester or modified spark plug, check for spark at 2 spark plug wires. If no spark results, see System Testing. If spark is noted on one or both wires, check for dwell increase from low to high RPM.
  2. Check pick-up coil with ohmmeter leads attached to Green and White wires, removed from HEI module. If reading does not indicate between 500-1500 ohms, replace pick-up coil. If pick-up coil reading was satisfactory, and dwell did not increase, replace electronic module.
  3. If pick-up coil was satisfactory, but dwell increased, check fuel, spark plug wires, distributor cap, rotor or spark plugs.
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