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Secondary Circuit Check

CAUTION: When checking secondary voltage, do not remove spark plug wires from spark plugs No. 3 on 4-cylinder, No. 1 or 5 on 6-cylinder and No. 3 or 4 on V8 Engines.
  1. Disconnect coil wire from distributor cap. Use insulated pliers to hold wire approximately 1/2" from engine block or intake manifold.
  2. Crank engine and check for spark at gap. If no spark occurs, turn off ignition switch, and check resistance of secondary coil windings. See IGNITION COIL RESISTANCE CHECK, SECONDARY RESISTANCE. Replace ignition coil if outside specifications.
  3. If spark occurred in step 2), connect coil wire to distributor cap. Remove wire from 1 spark plug. Using insulated pliers, hold wire 1/2" from engine head while cranking engine. Check for spark.
  4. If spark occurs, check for fuel problems or incorrect timing. If no sparks occur, check for defective rotor or distributor cap or for defective spark plug wires.
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