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System Spark Check

  1. If vehicle will not start or does not run properly, ensure first that starter fuel system are operating correctly. If so, check secondary voltage.
  2. Remove coil high tension wire with suppressor from distributor cap. Hold wire approximately 3/8" from engine ground, using insulated pliers.
    CAUTION: Wire must not be hand held for this test. Each end of wire should be equipped with a 1000-ohm suppressor.
  3. Crank engine and check for a constant blue spark at gap to ground. If there is no spark, proceed to IDLE STABILIZER CHECK . If there is a good spark, but engine would not start, suspect externally damaged ignition coil.
  4. Check to see if sealing compound is oozing from coil housing. If damaged, replace ignition coil and proceed to CONTROL UNIT VOLTAGE CHECK .
  5. If coil was not damaged, check coil high tension wire, distributor cap, rotor, spark plug wires, spark plugs, (fuel system and engine mechanical components have already been determined okay).
  6. Rotor arm resistance should be 600-1400 ohms. Resistance of spark plug connectors should be 600-1400 ohms (not suppressed) or 4000-6000 ohms (suppressed). Suppressor (distributor side of ignition wire) resistance should be 600-1400 ohms. Replace defective parts if not to specifications.
  7. If components in step 5) were not defective, check for proper ignition timing, centrifugal advance, or vacuum advance. If okay, problem is not with ignition system. If ignition timing is not to specifications, adjust timing or repair ignition distributor.
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