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Preliminary Steps: Notes

  1. Visually inspect engine compartment to ensure that all vacuum hoses and spark plug wires are properly routed and securely connected. Examine all wiring harnesses and connectors for insulation damage, burnt or overheated wires, and loose or broken terminals.
  2. Ensure that battery is fully charged and that all accessories are off. Check that TFI ignition module is securely fastened to distributor base. Obtain Spark Tester (D81P-6666-A). See Fig 1. A spark plug with a broken side electrode is NOT recommended as it may lead to incorrect results.
  3. When inspecting wiring harness, both a visual inspection and a continuity check should be performed. When checking continuity perform a "WIGGLE" test to assist in finding intermittent faults.
Fig 1: Spark Tester
G54442Courtesy of FORD MOTOR CO.