No start, no spark
Cheapest way to do this is to replace the ignition module for about $20. The 1986-89 Fords were known for having a defective ignition system. Ford called it a TFI, Thick Film Ignition module, and many of these were known to cut out at inopportune times, highway speeds, etc., and cause accidents or fires. Replacing it with an aftermarket ignition should cure the problem. There is a test for ignition modules but I am not sure how it is done on the Fords. On GMs, you measure resistance across certain terminals. High or infinite resistance indicates a bad coil.
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